Gordon Brown, UK chancellor of the exchequer, yesterday guaranteed there would be no weakening of the ruling Labour party's stance on euro entry if it won next week's general election.

He insisted that a decision to join the currency would first require "clear and unambiguous proof" that the move was in the UK's economic interest.

As Labour and the opposition Conservatives battle for the business vote in the final phase of campaigning ahead of the May 5th election, the chancellor said it had been right for the UK to stay out of the euro in Labour's second term and that nothing must be done to put the country's economic stability at risk.

"In the next parliament, and at all times, I can guarantee that the five tests [ on euro entry] would have to be met and the results be clear and unambiguous," Mr Brown told the British Chambers of Commerce's annual conference. "Stability and the national economic interest will always come first."

The chancellor's comments do not signal any change in the Treasury's commitment to review the five economic tests at some later date. But the timing of Mr Brown's words, coming just 10 days before polling day, could be seen as a strong signal that Labour would not move to take the UK into the euro in its third term.

The timing of the comments may also signal that Tony Blair, UK prime minister, has now given up on his ambition to take the UK into the euro before he stands down as prime minister.

Mr Brown's words are also designed to head off any chance for the Conservatives and their leader, Michael Howard, to exploit eurosceptic sectors of the business community by stating that they are the only party intent on keeping the pound.

Mr Brown clashed with business over the extent to which Brussels has been responsible for the growth in regulation under Labour.

The chancellor told the conference that Europe had generated "40 per cent of major new regulations" and "most of the new employment legislation, which has been a problem".