The chancellor will today make his long-awaited statement on Britain's prospects for joining the single currency.

While admitting that a majority of the five economic tests have not yet been met, Gordon Brown will attempt to pacify euro supporters by launching the government's long-postponed campaign to create a "patriotic pro-European consensus".

The prime minister and the chancellor will tomorrow hold a joint press conference in Downing Street.

"Tony Blair and I have decided - and the Cabinet agreed on Thursday - that after the statement tomorrow we should put the pro-European case. I believe we can unite the British people around a pro-European consensus which I believe is vital for the future of this country," the chancellor told the BBC's Breakfast with Frost yesterday.

Writing in today's Financial Times, Peter Mandelson challenged "every senior minister" to promote Britain's active participation in Europe.

"Those who already believe Britain is a less than fully convinced European partner and whose view was confirmed by our siding with the US, will be strengthened in their objection to British 'exceptionalism'," he says.

Today's statement will be accompanied by the largest amount of paperwork to come out of the Treasury in a single day.

Journalists and MPs will receive 1738 pages of technical studies, a 250 page assessment and a new national changeover plan.

More than 50 independent economists have contributed.

Meanwhile, Gus O'Donnell, the most senior official at the Treasury, has written to today's FT to welcome the influence of economists on Britain's public life.

Today's Independent gives over its front page to an editorial on the issue, describing the decision to delay entry as a "tragedy" and a "missed opportunity".