Cards on the table: I'm an ex-smoker. A late starter, admittedly; I inhaled my first lungful in France at the age of about 14, but didn't succumb properly till about midway through university. I was into my stride by the mid-80s, loving the classic burgundy-and-gold elegance of the old Dunhill Reds.

It was an international affair. In Amsterdam, where tar-stained ceilings in fug-filled cafes reminded you that smoking was Holland's national sport, everyone rolled their own. I fell for Van Nelle Zware Shag, the only tobacco, so the gale-lashed Dutch fisherman in the ads used to say, that you can still taste in a storm force 10.

In Scandinavia, I switched to Petteroes No 3, a sweeter blend from H Petteroe Tobaksfabrik in Oslo. In Paris, I flirted for a while with the husky Gallic charms of Bastos Bleu Sans Filtre, before finally returning to my first love: un paquet de Dunhill Rouge, s'il vous plait. Obviously, I tried to stop. Often. Giving up is easy, I'd say: I've done it dozens of times. Eventually, I did.

But the reason for recounting this is that it all happened quite a long time ago now, at a time and in places where smoking was in no way a reprehensible activity (my first encounter with France's interpretation of the no-smoking area, in about 1980, was a sign in the corner of a restaurant that read, roughly, "We apologise to our valued customers, but the law regrettably obliges us to reserve these tables for non-smokers.")

Now, of course, things are different. These days, it's actually quite difficult to be a smoker. Even Paris - even, so help me, Amsterdam - has smokefree legislation. In Britain, there's no more tobacco advertising, cigarette packets inform you bluntly that smoking their contents will kill you, it's illegal to sell tobacco products to the under-18s, you can get help with quitting on the NHS, and, most striking of all, it has become illegal to smoke in pubs, clubs, restaurants, any enclosed public space.

That's not the end of it. Over the coming year, smokers are going to have to get used to seeing an attractive selection of pictures on the back of their fag packets. One is of some poor sod, chest riven open, undergoing open heart surgery. Another is a frankly repulsive close-up of a throat sprouting some gruesome, fleshy growth. A third shows someone's foul and cancerous mouth, all missing and blackened teeth and dark, diseased tongue.

There are 14 of these shockers, and every cigarette packet sold in this country will have to carry one of them by October 2009. We're in the vanguard here, the first EU country to make photo warnings compulsory on all tobacco packaging. (In Canada, where they were launched in 2001, 31% of ex-smokers say they helped them kick the habit.) In fact, we're pretty good across the whole anti-smoking front: since the government's 1998 white paper Smoking Kills, Britain has become recognised as the European leader in tobacco control.

In this country, in 2008, smoking is basically seen as antisocial and, increasingly, socially unacceptable. When I took my first puff, in the mid-70s, you could light up pretty much anywhere you liked and no one would raise an eyebrow: bus, cinema, dinner table. These days, guests don't even bother asking their host if they might smoke. They withdraw, discreetly, and slip outside (where they're not safe from abuse either; these days, smokers routinely get told off for indulging in the open air).

All of which should mean that smoking was a rather less widespread activity in Britain than it still is. Certainly the atmosphere is hostile enough to committed smokers for their tireless lobby group, Forest, to complain of "persecution, bullying, humiliation and coercion" in regard to a habit that never has been, and in the foreseeable future is unlikely ever to be, declared illegal. Despite all the anti-smoking measures of the past 10 years, says its director Simon Clark, smoking rates have fallen by only a few percentage points. "We're all for education about the health risks of smoking, but this has now gone way beyond that," Clark says. "I think it's a sign of desperation. The government seems determined to humiliate smokers until they behave in a state-approved way. Maybe the anti-smokers can knock one more percentage point off the smoking rate, but is it worth it for the bully society we're creating?"

For sure, many fewer of us light up than in 1948, when 82% of British men and 41% of British women were regular smokers. By 1974, 51% of men and 41% of women smoked; by 1992, it was 28% of us; in 2005, 24%. Since the Smokefree England legislation came into force in July last year, a further 235,000 people have given up with the help of NHS Stop Smoking Services. According to Professor Robert West's Smoking Toolkit Study, some 400,000 people have quit in the wake of the ban.

But that still leaves 23% of men and 21% of women, or just over 9 million people still smoking. They must know, or at least be aware of, the risks they are running: half of all regular cigarette smokers will die from their habit. Each year, some 114,000 smokers in the UK die from smoking-related causes. Smoking remains the single biggest cause of preventable deaths in Britain, killing more each year than alcohol, obesity, road accidents and illegal drugs together.

So the real question is: who still smokes? The answer, according to Beyond Smoking Kills, a report published today by the broadly endorsed pressure group Ash, is the poor. "The health inequalities involved are perhaps the most striking thing about smoking in Britain today," says Deborah Arnott, its president. "The more deprived your circumstances, the more likely you are to smoke."

According to Professor Martin Jarvis, a psychologist at University College London and a leading specialist in the field of smoking and health inequality, this is not a question solely of income: every main indicator of a lower socio-economic status is likely, independent of each of the others, to predict a higher rate of smoking. If your educational level is below the average, you are more likely to smoke. If you live in rented or overcrowded accommodation, you are more likely to smoke. Ditto if you do not have access to a car, are unemployed, or on state income benefit.

"There's already a considerable social gradient simply in who starts smoking," says Jarvis. "But the main, really steep gradient is in who manages to stop. People in depressed circumstances are basically far less likely to give up. This isn't to do with motivation - they actually want to quit just as much. They just don't seem to be able to. The more deprived you are, the more dependent you are on nicotine, the more nicotine you take in."

Today, 17% of men and 14% of women in professional and managerial occupations smoke. In routine and manual occupations, the figures are, respectively, 31% and 28%. In the most deprived areas of England, in parts of Knowsley and Liverpool, up to 52% of people smoke. In the least deprived, in places such as Rushcliffe, south of Nottingham, and Heatherside and Eastleigh in Hampshire, as few as 12% do. Some 48% of men in the poorest social class die before reaching 70, compared to just 22% in the most affluent; smoking is generally estimated to account for at least half that terrible difference in life expectancy.

Several theories are advanced as to why people in deprived circumstances are so much more likely to smoke. The habit, says Jarvis, might be considered a form of self-medication: nicotine (and it is pretty much accepted that nicotine is why people smoke) is "doing something for you that you value. Many smokers think it helps them deal with stress, reduce anxiety. Of course, there's very little evidence that it actually does that." Mainly, it seems, all smoking a cigarette does is relieve the (temporary) withdrawal symptoms you get from not smoking a cigarette.

There's also the economic argument. A smoking habit of 20 a day costs between £1,700 and £1,900 a year. Poorer smokers will spend a disproportionately large share of their income on cigarettes; research from 2003 showed that the poorest 10% of households in Britain spent 2.43% of their income on smoking, against 0.52% for the richest 10%. A 2004 Family Spending survey found that among the most deprived families of all - single parents on state benefits - three out of four smoke, a habit that costs them more than one-seventh of their total disposable income.

"One of the things that means, says Jarvis, "is that if you're a poor smoker you're going to want to maximise the 'hit' you get from each cigarette, because it represents a larger chunk of your income. The amount of nicotine you can get from each cigarette is very elastic; it depends how hard you puff, how deeply you inhale, how much of the cigarette you smoke." Across all age groups, and even if they smoke the same number of cigarettes, poorer smokers take in markedly more nicotine that wealthier ones. "Smokers in lower socio-economic groups," says Jarvis, "are addicted to a higher hit. Their nicotine addiction is stronger."

Finally, poor families, being more likely to smoke, are more likely to produce future smokers. In general, fewer and fewer children in Britain are smoking: from 13% of 11- to 15-year-olds in 1996, the figure has now fallen to around 6% (including 9% of 14-year-olds, and 15% of 15-year-olds). But according to a recent Dutch study, the children of smoking parents are four times more likely to smoke themselves. And emulation or experimentation at an early age is a clear predictor of later smoking; a 2004 US survey found that smoking just one cigarette in early childhood more than doubles your chances of becoming a smoker by the age of 17.

The public smoking ban will, experts believe, have gone some way to reducing the gap in smoking rates between social classes: the most recent figures show the decline in smoking recorded since its introduction occurred across the board, regardless of class, age or gender. But the government's future tobacco control policies should, Ash's Arnott says, clearly include measures - including more free help in giving up - targeted specifically at deprived groups.

"Smoking's an amazing area," she says. "Nobody really knows how best to ensure people eat less, and eat healthily; how to encourage them to drink less, or take more exercise. But with smoking we do know what works: since 1998 there's been a really very significant decline indeed. What we're doing is working; we just need more." Jarvis says that the present government's record in slashing smoking rates is "probably one of its finest achievements".

So how to move forward? If the British public care deeply about questions of individual liberty, and will not in general support anything that unduly restricts it, most will back measures that might help cut tobacco consumption. Arnott cites the case of the public smoking ban, the idea of which was supported by just 20% of people in 2003, but this April by fully 78%. "Big majorities also support raising tobacco prices by more than inflation, halting sales from vending machines, and ending point-of-sale displays," she says.

"But perhaps the best indication of how the public feel about the whole smoking issue is the fact that compliance with smokefree legislation in Britain is so spectacularly high - more than 98%. Compare that with the proportion of people who comply with the 30mph speed limit in built-up areas. That's only around half."

Today's Ash report, 10 years after the important white paper Smoking Kills, estimates that smoking is costing the NHS in England some £2.7bn a year. It calls for a comprehensive new national tobacco strategy and tough targets, including a smoking rate of 11% in the adult population as a whole by 2015. Among its key recommendations are a ban on all tobacco product branding (which means selling cigarettes in blank packs, except of course for a graphic health warning); prohibiting retailers from putting cigarettes on display (the huge displays in tobacconists and supermarkets are, campaigners say, a "powerful promotional tool that encourages impulse buying"; banning them would essentially mean stocking cigarettes under the counter) and outlawing tobacco in vending machines, which are used by about 20% of under-age smokers.

The report also calls for a properly resourced fight against tobacco smuggling, which accounts for about 13% of the cigarettes and 20% of the hand-rolling tobacco smoked in Britain. It wants tobacco to be more expensive to buy than it is now (historically, cigarettes are 60% more affordable than they were in the 1960s). It would like to see deprived and marginalised groups given priority in all stop-smoking campaigns, and, for smokers who are really unwilling or unable to quit, it would like pure nicotine products such as gums and inhalers that deliver nicotine as effectively as cigarettes, but without the fatal by-products that come with smoking to be more widely available, more competitive, and even free on prescription.

Will all this work? The problem, as the number of dedicated smokers in Britain continues gradually to dwindle, is that those that remain will prove more and more resistant; any measure perceived as aggressive could just as easily prove counterproductive. The evidence from a sample of smokers accosted on the streets near the Guardian the other day was, certainly, not entirely encouraging. Confronted with those unpleasant picture warnings, most did not feel they would persuade them to stop.

"They might stop a few young people starting, I suppose," volunteers Adam Riley, 41, sucking on a B&H outside the sandwich shop. "But I can't see them doing much for me. They're horrible, yes, course they are, but we already knew the risks, didn't we? What's this going to add to that, beyond making us all feel even more persecuted?"

Perched puffing on the steps outside their dance school, Jackie, Mandy and Felicity were similarly unimpressed. "If you were already thinking about giving up, this might give you the extra incentive," concedes Felicity, 17. "They are revolting, though, aren't they? Ugh. That throat one . . . I don't want to look at that too often. But I think if you've kind of rationalised smoking, then you'll just shut your eyes to these too." Mandy says she's only going to smoke for three or four more years, anyway. "I'll be fine as long as I stop then. None of that stuff is going to happen to me, no way."

David Levy, unemployed and 40, says he won't be quitting any time soon, whatever the government comes up with next. "I'm a smoker. I have been for a very long time and I enjoy it. These won't stop people like me."

· This article was amended on Thursday October 9 2008. Britain will not become the first EU country to require photograph-based health warnings on cigarette packets next year as we said in the article above. That is already the case in Belgium and Romania. It will, however, become the first to make picture warnings compulsory on all tobacco packaging. This has been corrected.