As we arrive for our interview with Ken Clarke, he is groaning about having to squeeze into his black tie for a dinner. The Conservatives' man of the people is more comfortable in shirt sleeves and suede shoes. He prefers dingy jazz cellars to swanky yachts. He loves birdwatching on the moors but he would never go shooting in plus-fours - “the idea would be hilarious”, he says. For years, he played snooker every week with his son - “I should have been brilliant after a lifetime of dedication,” he says, “but I was never any good.”

Even when he was Chancellor, he chose to spend the party conference week in a B&B rather than the five-star hotel favoured by his colleagues. When he left the Government he was filmed driving his own furniture around Nottingham in a white van.

“I can't be attacked for being a toff. I am very provincial and very suburban,” he says. “No one ever said I was too posh.”

It's not that he doesn't spend money but he says: “I spend my money on different things. I'm not particularly frugal. I spend a higher proportion of my income on foreign travel than anyone I know. I go to rainforests. If I go to the seaside it's because I have a grandchild but I don't actually go to the beach - I stay on the terrace, smoke a cigar and read.”

He is so laid back he is nearly horizontal - when we ask what he has been reading recently, he says: “Certainly not John Maynard Keynes. I'm reading a history of Anglo-Saxon England and a biography of Michael Foot.”

There are some who think that this big beast should be dragged out of the Tory jungle to replace George Osborne. But Mr Clarke insists that it would be a huge mistake for David Cameron to dump his Shadow Chancellor. “The attacks on George are foolish and I don't agree with them. I think he is very good. It would be bizarre for David to move George. Politically it would look weak. People keep using me as a stick to beat George with. I'm not particularly flattered. I've realised it's just Bash George fortnight.”

Mr Osborne is not, in his view, too young for the Treasury. “People always used to say I should acquire more gravitas. And I don't think he is too thin. I thought the modern fashion was to be stick-like - although some of us rally to the cause of obesity.”

Nor, he thinks, will the class attacks resonate. “If I had my way I would buy up all the negatives of the Bullingdon Club that exist and burn them, but every politician has pictures of themselves doing something stupid in their teens.”

He defends the Shadow Chancellor's decision to issue a warning of a run on the pound. “I was amazed anybody bought the idea, being spun by Gordon's people, that there was some convention that you don't talk about the pound - that's daft. I remember Harold Wilson used to get frightfully upset about people selling sterling short but that didn't stop people talking about the pound because the pound was weak.”

Although he has been surprised by the vociferousness of the attacks on Mr Osborne, he says: “You'd better get used to it, George - there'll be a few more before you've finished. As a veteran I say, ‘Been there, done that', and it will happen to him again.”

There may, he believes, be a political motivation behind some of his own party's criticism. “David and George have made us look like a potentially governing party again but the message has not quite spread to some of my colleagues. These are the people who think you've got to promise tax cuts to win any election.

We've fought elections on tax cuts when you can't afford them and usually we've lost - we did actually win one in 1992, which was a considerable embarrassment to me when I was Chancellor because there wasn't the slightest chance of any tax cuts.”

He admits that it could be difficult to resist a return to Government if he were offered the job of chancellor in a future Cameron administration. “It's rather fanciful to go down that route, but everybody who is offered the chancellorship thinks about it and of course I wouldn't just turn it down peremptorily.”

Having steered Britain through the end of one recession, he would relish the chance of fighting another. “It's a pity I'm not chancellor at a time like this because I like a crisis. It gets the adrenalin going. This one really is tricky, so it would be fun to be involved.”

Joining the front bench in opposition, though, has no appeal. “Dave asked me to be Leader of the House when he took over and I said no. I prefer to be a backbencher. It's tedious being an opposition spokesman. You have to do one subject - you can't suddenly say, ‘Sorry I'm not here next week, I'm in a forest somewhere in West Africa'.”

Despite his loyalty to the party leadership, he is not afraid to put forward his own ideas. The Government should, he says, consider cutting VAT to 15 per cent in the Pre-Budget Report on Monday - an idea that is certainly not Tory party policy. “If it's possible to afford a fiscal stimulus I would go for VAT because the only case for a fiscal stimulus is to stimulate spending and consumer demand, so the tax on spending is the one to go for. But it should be temporary.”

Mr Osborne is opposed to a tax cut funded out of borrowing, but Mr Clarke says that such a fiscal stimulus should not be ruled out. “There's no point in being ultra-orthodox. A lot of people are going to be hurt by a dreadful recession. If you think a fiscal stimulus is going to do any good then you could strive to see if you can afford it.”

However, he says: “If Alistair Darling borrows a lot of money, sterling will nosedive and the long-term interest rates will go up. If that's the case, you can't afford it.” There are, he detects, tensions between No10 and the Treasury.

“Alistair Darling could be quite a good Chancellor if Gordon ever gave him the job. Gordon is rampaging around, talking about public works and tax cuts and giving a completely spun version of the G20 meeting, claiming it virtually instructed him to go for a big fiscal stimulus when it didn't at all. Then you get Alistair giving far more cautious Treasury-laden words about having to pay for these things.”

The voters will, he thinks, tire of the Prime Minister's superhero rhetoric. “Gordon Brown's banking package, the one that saved the world, hasn't worked any more than Hank Paulson's buying toxic debt has worked. We keep having ‘this is going to save the world' moments and they're all useless.”

The priority should, in his view, be small businesses and mortgage holders. “The country is full of small companies that can't get the ordinary credit to keep their business going. If I was in the Treasury I'd be concentrating on getting the lending going again.”

There is no point in demonising the bankers, he says. “I don't denounce these spivs and fat cats. People make mistakes. But if you were taking an extraordinary calculated risk motivated by personal greed, you tend to get unpopular.”

He does not know whether we are about to enter a depression, but says: “I think this is going to be the longest, hardest recession of my lifetime. There's no one alive who's seen anything like this before - it's the worst banking crisis for 100 years or more.”

The country, he says, needs to be ready for a long haul. “It's very nice that we're all saying to each other that it will be better in 2010, but there's no factual reason why that should happen. Once recovery starts it will be quite feeble. You have to nurture recovery.”

In his view, there is no point going on a Keynesian spending spree. “That's useless. It's pork barrel. It takes two or three years for any money to get into public works. The recession is long over by the time your useless road or runway is ready.”

The Government should instead be going through its expenditure with a fine-tooth comb. “I don't think the new Labour Government understands what a proper spending round is like. They have increased expenditure beyond the capacity of departments to absorb it. Much of the money has gone on the payroll and a proliferation of useless quangos carrying out useless activities. I don't think it's the duty of the Government to tell me how to eat and shop.”

The public will see through any lavish spending and tax-cutting plans. “When the Government has got itself into a mess like this, I would despair if people were just prepared to take bribes. I shall get more weekly fuel payments. I will take the bribe but it will not affect my judgment.”

This is why Mr Clarke is still prepared to squeeze into his dinner jacket two or three times a week, to spread the word that “Gordon's not working”. As the man who got Britain out of the last recession, he wants to make sure that his voice is heard.

The world according to Ken Clarke

Roundhead or cavalier? Cavalier
Yacht or rowing boat? Neither
Beach or moor? Moor
White van or Bentley? Neither
Plus-fours or suit? Suit. The idea of me in plus-fours would be hilarious
Golf or cricket? Cricket. I hate golf
Adam Smith or John Maynard Keynes? They both agree with each other. Leftwingers have misused John Maynard Keynes laughably
Curry or caviar? Curry

CV

Age 68
Education Nottingham Hill School, Gonville and Caius College, Cambridge, where he was chairman of the Conservative Association and President of Union
Career Health Secretary under Margaret Thatcher. Education Secretary, Home Secretary and Chancellor under John Major. Unsuccessful candidate for leadership in 1997, 2001 and 2005
Family Married Gillian in 1964. They have a son and a daughter
Notable As President of Cambridge Conservative Association, he invited Sir Oswald Mosley to speak. His contemporary, Michael Howard, resigned from the association in protest

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