Gordon Brown has denied claims that he is ready to block Britain's entry into the single currency.

The chancellor told the BBC's Breakfast with Frost yesterday that the Treasury's assessment of the five economic tests for membership had not started, although extensive preliminary work on the implications of joining the single currency had begun.

"The assessment has actually not started. We are doing a tremendous amount of work. This is the most difficult, the most important economic decision that this country has had to make on economic policy," he said.

His statements make it unlikely that a euro decision will be announced in the forthcoming Budget.

Matthew Taylor, the Liberal Democrat Treasury spokesman, said: "It shouldn't be a question simply for the chancellor. It's time for the British people as a whole to have their say on whether or not Britain joins the euro."