Britain's Prime Minister, Mr Tony Blair was loudly booed by traders in London's financial district yesterday when he ventured onto the floor of a bustling exchange.

The harsh reception reflected traders' unhappiness with how Mr Blair's new Labour government has handled the issue of when and if Britain will sign up to European economic and monetary union (EMU).

They booed and hissed Mr Blair when he and three foreign leaders appeared on a balcony overlooking the trading pits at the London International Financial Futures and Options Exchange (LIFFE).

"He's got a bit of a nerve coming down here after what (Chancellor Gordon) Brown did to us on Monday," said one trader of British government debt. "I lost a fortune."

British financial assets were hit hard by a combination of weekend press reports, contradictory briefings from government spokesmen and comments from Mr Brown himself which suggested Britain would not sign up to EMU before 2002.

Some analysts say LIFFE's role as the leading exchange in Europe will be in a particularly vulnerable position if Britain is not part of EMU.

"If he really does back Britain, he can't leave the markets guessing like this," said a trader at a major British bank.

But as Mr Blair toured the floor of the exchange, some of the younger traders seemed to be thawing.

Youthful autograph hunters crowded round the prime minister, who was escorting Australian Prime Minister, Mr John Howard, Sri Lankan President, Mr Chandirika Kumaratunga and Ugandan President, Mr Yoweri Museveni.

A hasty clean-up of the LIFFE floor meant Mr Blair did not have to negotiate the usual piles of screwed up newspapers, old deal tickets and chocolate wrappers - but nothing could stop the cries of "sell" as he passed the pits.

The issue of Europe was never far away. One independent trader leaned over the British debt pit to shake Mr Blair's hand as he left the floor.

"You've got to be strong over Europe, Tony," he said. "But we've got to know one way or the other."