Alistair Darling has warned that Britain's economic downturn will be the worst in 60 years.

The Chancellor said it will be "more profound and long-lasting than people thought" amid the worst global economic conditions.

Mr Darling also admitted that ministers were partly to blame for voters' frustration because they had "patently" failed to explain the problems.

The comments are the Government's grimmest assessment yet of the situation, and come after a Bank of England policymaker warned that unemployment could hit two million by Christmas.

Mr Darling said: "This coming 12 months will be the most difficult 12 months the Labour Party has had in a generation, quite frankly.

"We've got to rediscover that zeal which won three elections, and that is a huge problem for us at the moment. We really have to make our minds up; are we ready to try and persuade this country to support us for another term? Because the next 12 months are critical. It's still there to play for."

The Chancellor played down the prospects of an early reshuffle by Gordon Brown, and speculation that he could lose his job when the Prime Minister does shake up his team.

However, Mr Darling stressed that Mr Brown was one of his oldest friends, and he has confidence in his abilities.

Meanwhile, Shadow Chancellor George Osborne said: "Who is telling the truth at the top of Government?

"The Prime Minister says the economic situation isn't as bad people think and that Britain is well placed to weather the economic storm, but the Chancellor says we are at a 60 year low.

"Gordon Brown has briefed out stories that he has an economic recovery plan all worked out, meanwhile the Chancellor says the downturn will be more profound and long-lasting than people thought.

"It's not clear whether Alistair Darling meant to tell us the truth about the mess 10 years of a Labour Government has left our economy in, but he has certainly let the cat out of the bag."

Liberal Democrat Shadow Chancellor Vince Cable said: "The Government is finally being honest with itself and with the British public about the scale of the problem and recognises that the British economy is not simply a victim of external events.

"The next step must now be for the Government to admit that those aspects of the economy which it believed were its sources of strengths are now clearly its weaknesses."

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