Why big loan is no problem for Blairs

With home buyers scared off by fears of a crash and the rising cost of borrowing, the Blairs' decision to to shackle themselves to a mega mortgage might seem perverse.

But they are no ordinary couple and it is no ordinary house - a £3.6m property in exclusive Connaught Square in the City of Westminster with a W2 postcode.

Based on what we do know and, inevitably, assumptions, mortgage brokers who deal in such properties said that an estimated £11,000 to £12,000 a month Tony and Cherie will be shelling out would be covered by the rent they are likely to receive (from, say, an executive willing to pay for the kudos of living in the PM's home) until they want to move in, perhaps five years from now.

The £178,922 Mr Blair earns as prime minister and an MP would not secure the £2m-plus brokers reckon the couple have taken out. But Mrs Blair's earnings as a QC and part-time judge almost certainly run into several hundred thousand, and she will pocket a six-figure sum from a book on prime ministerial spouses.

The couple sold their past home in Islington, north London, for £615,000 in 1997, and their present living expenses are fairly minimal, as he has free tenancy of a Downing Street flat and a large country house, Chequers. He took a mortgage to buy his constituency home in Sedgefield for £30,000 more than 20 years ago, but receives an allowance. "I'd guess they would quite easily have been able to get together at least a million quid deposit, plus the stamp duty," said Simon Tyler at the broker Chase De Vere Mortgage Management.