INTEREST rates would be higher in an independent Scotland, the world's biggest lender to governments warned last night.

In a BBC 2 programme, Mike Amery of Pimco, the biggest investor in government bonds worldwide, is asked if the government in an independent Scotland would have to pay higher rates. He replied: "Our best estimate, assuming a ­reasonably even split of assets and liabilities, would be the interest rate paid by a Scottish Government would be between half and one per cent more than the UK currently pays."

Blair McDougall for the Better Together campaign seized on the comments, saying: "An increase of one per cent on interest rates would put the average Scottish mortgage up by £1,300 and add around £120 a year to credit card, catalogue and store card bills.

"That is because, as Mr Amery points out, an independent Scotland would be regarded as a higher risk investment. We do not need to take that risk if we remain part of the UK as we will remain part of the pound, one of the world's leading currencies."

But earlier this year, Nicola Sturgeon, the Deputy First Minister, insisted there was "not a scrap of evidence" to suggest borrowing costs would be higher in an independent Scotland.