Britain is facing a mass exodus of nurses. Hospital staff who came from overseas several years ago to help out the NHS are now being lured to other countries where wages are much higher.

The warning has been made by the Royal College of Nursing which has discovered that half of the foreign nurses in Britain are now considering jobs in other countries.

Decisions by them to depart would leave the NHS with a huge headache. Although many more people are now going into nursing training, a substantial number decide not to stay. Homegrown nurses, particularly junior staff, may also be tempted to go abroad.

The wage differential is particularly tempting for nurses on the lower grades of the profession. 'We have Filipino and Indian nurses who may have come to the UK via Saudi Arabia and the Emirates some time ago, who are now looking to move onto other countries,' said Josie Irwin, head of employment relations at the RCN. 'They are tempted by offers from America and Australia, who are recruiting staff aggressively.'

An experienced specialist nurse on around £25,000 here would be offered £10,000 more - plus accommodation and opportunities to travel - in the States.

Despite a 23 per cent increase in the nursing workforce in England since 1997, the RCN says the government needs to take urgent action to avoid a return to the chronic shortages of the early 1990s.

The RCN's annual Labour Market Review highlights an ageing nurse population with an average age of 44. While there are around 20,000 new UK entrants to the nursing register per year, the number of nurses retiring in the near future raises the issue of whether this is enough.

Some 45 per cent of new entrants over the past four years have been from overseas, including more than 12,000 in the past year.

The government claims to have done much to make nursing attractive, with better conditions and fairer pay. But despite increased numbers, pay still lags behind that of other countries.