Julia Harris, mortgage expert at Moneyfacts.co.uk, the independent financial comparison site, commented: It is very rare to see a lender increase its standard variable rate (SVR) outside a base rate change. It could very well be the first sign that the mainstream ‘prime’ mortgage is feeling the pinch of the credit crisis.

The bank claims that even with this latest increase, its 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.