Gordon Brown has pledged to fight for a euro Yes vote if his five key tests are met.

The chancellor told the BBC that both he and Tony Blair are united in their determination to "make the right decision in the right way".

He said that, if the five tests are met, he will work just as hard as the prime minister to achieve a Yes vote in a referendum.

But the tests will remain "the centrepiece" of the Cabinet decision and his own announcement to the House of Commons on June 9, he said.

And it will be the results of the tests, not political "dogma" which determine whether ministers recommend British entry.

"The five tests effectively define the national economic interest for our country," Brown claimed.

"It is a guarantee that we can ensure jobs, investment and the future profitability of industry and the prosperity of the country.

"When I make the statement to parliament on June 9, the focus will be on these five economic tests that define the economic interests of the country."

The chancellor challenged media reports of his own euro scepticism by maintaining that he was committed in principle to entry into the single currency.

"Of course, if there were a referendum, then I would be urging, on the basis of the five-test assessment, a Yes vote," he said

The interview came as part of a concerted government effort to refute media reports that Blair and Brown are divided on euro membership.

There had been suggestions that while the prime minister wanted to keep open the option of a referendum later in this parliament, the chancellor had sought to rule it out until after the next election.

But both men have denied reports that they are at loggerheads over the euro.

In a joint statement issued on Friday, Blair and Brown said they were not "at odds" on membership of the single currency.

Blair said he was not determined to call a euro referendum "come what may".

And Brown added that it was "simply not the case" that he was opposed to a euro vote in this parliament whatever the circumstances.

"Once a decision is taken, the prime minister and chancellor will be on exactly the same page, in total command of all the arguments and confident of winning support for the final agreed position," the statement said.

Both men also insisted that the Cabinet would have a key role to play in the eventual decision.

That pledge came as senior ministers were preparing to spend the weekend reading the Treasury's comprehensive research on possible British membership of the euro.

Members of the Cabinet have been given around 2000 pages of economic analysis to read, ahead of next Thursday's discussions on the single currency.

The consultation process will continue until the final decision is take at a special Cabinet session to be held on June 5 or 6.

That will be followed by an announcement in parliament on June 9.