The largest lender in Britain is continually clamping down on borrowers who are currently on cheap mortgages by "forcing" them to move over to more expensive deals if they switch homes.

The development by Halifax could means that over a thousand families might end up having to pay some hundreds of pounds more in monthly mortgage installments, despite the authorities keeping interest rates at an all-time low, near zero level.

Experts are of the opinion that the move is the latest sign of lenders looking to squeeze greater margins out of owners of residential properties in order to help boost their own profits.

Borrowers who near the end of their mortgage automatically fall into a lender's Standard Variable Rate deals, and with the bank no longer allowing SVR customers to shift properties, they have to remortgage instead, which turns out to be more expensive.

“Customers who are currently reverting to rates as low as 3.5 per cent simply have little or no motivation to remortgage and closing the door to port these deals will only antagonize many potential home movers", said Darren Cook of Moneyfacts, a personal finance website.

Various lenders have now hiked their SVRs stressing that they are unable to keep up with the original deal on the back of the current market situation.