The government has denied reports of a rift between the prime minister and chancellor over British membership of the euro.

Liberal Democrats pointed to a possible conflict between Number 10 and Number 11 Downing Street on the issue, highlighting a paper that was published with last week's pre-Budget report.

It praised the existing macroeconomic frameworks in the UK, such as the independent Bank of England, and stressed Treasury criteria for convergence required to peg the pound against another currency, such as the euro.

The paper has been used by anti-euro campaigners to question whether the famous five economic tests could ever be met.

But fundraisers for the Britain in Europe campaign have begun setting up a high-tech headquarters in London modelled on New Labour's Millbank base that ran the 1997 general election campaign.

They are advising potential backers that it is worth making big-money donations and that the group will be ready for a poll "sometime in the next 12 months".

"These people didn't get rich by splashing a million pounds left, right and centre without thinking about it," said a spokesman.

One senior cabinet minister, who is a close ally of Tony Blair, has also signalled he expects a vote with "nine or 10 months".

Liberal Democrat Treasury spokesman David Laws claimed that the Treasury document indicated strained relations between Blair and Brown.

"Ever since the five tests were laid out in 1997, we have been given to believe that there was basically no difference between 10 and 11 Downing Street on the euro and it was just a question of timing when we actually met the five tests.

"But this Treasury document gives the impression that the Treasury itself really is very unwilling to trade in the system of UK macroeconomic management it has set up since 1997," he told the BBC Radio 4 Today programme.

"It gives the impression that in certain fundamental respects it thinks our system is better than that in the eurozone. This has been implied at other times, but it has never been laid out in this explicit way before.

"The question here is whether, aside from the five tests, there is now a fundamental division opening up between the Treasury and 10 Downing Street about policy on the euro."

However, speaking on the same programme, foreign secretary Jack Straw denied the allegations.

"The position on the euro was well set out and durably set out by Gordon Brown in his statement to the Commons on October 27 1997, setting out these five key tests," he said.

"We all have to wait for the Treasury's economic assessment, which will be made public by June of next year."