Are big banks short-changing consumers by failing to reduce mortgage costs?

Mortgage deals are 50%-60% more expensive than three months ago. Photograph: Andy Rain/EPA

Big high street banks stand accused of failing to pass on to customers the recent movements in the money markets that should have improved mortgage and savings rates.

Some lenders are offering fixed-rate mortgage deals that are 50%-60% more expensive than those they were selling three months ago – despite the fact the money market “swap rates” that largely determine the pricing of new fixed deals have fallen sharply since the highs which followed Kwasi Kwarteng’s disastrous mini-budget.