British Prime Minister Tony Blair has expressed his sympathy for British workers who lose their jobs to outsourcing, but says he is powerless to block new trends in the global economy.

Blair's comments follow the disclosure by UK insurance company Aviva, which trades as Norwich Union, that it will 'outsource' jobs to India as part of an axing of a total of 2,350 posts in Britain. It is threatening up to 500 of them will be compulsory redundancies.

Delhi and Bangalore will be the principal beneficiaries of Aviva's move, which has been described as 'deplorable' by the UK trade union Amicus.

Amicus says thousands of British workers had been given a Christmas present of an uncertain future.

Asked for his comments, Blair said he was 'desperately sorry' for anyone whose job was at risk, but outsourcing jobs abroad was just 'the way the world is today.'

"We have not tried to pretend to people we can stop what is happening in the global economy," he added.

Aviva says it hopes to be able to redeploy 80 per cent of the British staff affected, but the remainder face losing their jobs. They would not have a final figure on job losses, or which offices would be affected until next year.

Amicus has accused the company of pushing through the move without consultation with its members and says it will 'aggressively' fight the proposals, which it hoped would draw attention to the wider issue of companies moving jobs abroad.

The union warned of a walkout in the new year if workers vote in favour of strikes. "Creating a fear factor over job security for thousands of people three weeks before Christmas is unacceptable," said Karen Reay of Amicus.

Reay said the union does not object to jobs being created in India but opposes the outsourcing of British jobs serving the home market. Amicus claims 200,000 finance jobs could leave the country in five years.

She also warned the trend would harm the financial services sector in the same way Britain's manufacturing industry was mortally weakened in the 1970s and 1980s, leaving a skills gap for future generations which will harm the home job market long-term.

So far this year, Aviva has already shed some 1,600 jobs from its life and general insurance businesses. The company says its latest announcement will affect about 2,000 back-office, administration and IT staff and about 350 call centre posts.

Aviva currently employs 59,000 staff, including 33,000 in Britain. Its Norwich Union subsidiary will redeploy 700 jobs to Aviva's Indian operation in Delhi and Bangalore, where it already employs 1,200 workers.

Chief executive of Norwich Union Gary Withers said change had been 'on the agenda all year' and the move means 'good news for staff in the longer term.'

Withers said the company's priority is to re-deploy workers, explaining that it has an annual staff turnover of 4,500 and the option of moving staff between the different arms of its business.

Rejecting the Amicus claim that they owed a social responsibility to protect British jobs, Withers asked why financial services should be any different from other industries, such as car and clothing manufacturers or food and drink production houses.

"Aviva is a worldwide company and we're trying to use the benefits available."