The recent credit crunch is beginning to take its toll on mainstream lenders, which could mean mortgage rates are set to rise, it has been claimed.

Financial information group Moneyfacts.co.uk issued the warning after Standard Life Bank announced it is increasing its standard variable mortgage rate by 0.15% to 7.46%.

The group would not disclose how many customers will be affected by the change, but said it had made the decision in response to recent changes in the mortgage market.

Moneyfacts.co.uk said it is "very rare" to see a lender increase its SVR outside of a change in the Bank of England base rate, and it warned that it could be the first sign that mainstream lenders are now beginning to feel the "pinch".

Julia Harris, mortgage expert at Moneyfacts.co.uk, said: "Even with this latest increase, Standard Life Bank's SVR remains in line with the market average.

"While none of Standard Life's rates are directly linked to the SVR, the increase will still affect many existing borrowers who have reverted to a SVR once their deal has elapsed.

"For those already paying the SVR, this shock move should be the straw that finally breaks the camel's back and encourages them to find a better deal or, at the very least make sure the SVR is still the best option for them."

She also said that borrowers who had taken out a fixed-rate mortgage with the company may also be affected by the move, as anyone who had their mortgage arrangement fee added to their loan will be charged interest at the SVR rather than the fixed rate.

Ms Harris added: "This is a stark warning for anyone on an SVR rate or, indeed anyone with a rate linked to the SVR, as with many discounted rates.

"SVR is a managed rate, controlled by the lender, and it can and does move when base rate is stable."

Halifax and Abbey are among a group of lenders who have already increased the rates they charge on tracker mortgages for new customers as a result of the recent credit crunch.

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