High street banks have begun hiking mortgage rates for borrowers with large deposits, in a move that could add hundreds of pounds a year to the cost of remortgaging for wealthier homeowners. The shift comes as stubborn inflation figures dampen hopes of further interest rate cuts this summer. Over the past week, nine lenders — including Halifax, Nationwide, NatWest and Santander — have increased their fixed-rate mortgage deals, targeting products typically used by those with...