The chancellor and the prime minister yesterday launched a concerted campaign to sell euro membership to the British people.

Despite ruling out joining the single currency for at least a year, Tony Blair mounted a fresh bid to create a "strong pro-European consensus" in the country.

"It is time to make the argument for Britain in Europe," he said. "It is time to take on those who argue that to be pro-British we must be anti-European."

At the joint press conference in Downing Street, the prime minister added that "significant progress" could be made over the next 12 months in overcoming the remaining economic obstacles.

Pro-euro Cabinet ministers have been given "free rein" to go out and sell the benefits of the single currency to the public, the Times reveals.

But the public trust Gordon Brown rather than Tony Blair to tell them when the time is right to join the euro, according to a YouGov survey for the Telegraph today.

According to the poll, 61 per cent say they are against Britain joining the single currency - compared to 51 per cent a year ago.

Iain Duncan Smith claimed that the united front presented by the prime minister and chancellor was an attempt to show that the government was not divided.

"They used to say their policy was 'prepare and decide', now it is 'hope and pray'," the Conservative leader said.