Justin King Sainsbury's CEO

Justin King is the former CEO of Sainsbury's 

Prices in UK retailers could rise by a minimum of five per cent over the next six months, former Sainsbury’s chief executive Justin King has said.

King told BBC’s Newsnight that a return to inflation is inevitable due to the falling value of the pound and the UK’s reliance on imports.

'Around 40 per cent to 50 per cent of what we buy is sourced abroad in a currency other than the pound, so with the current rates of exchange we could expect those things to be about 10 per cent more expensive,” King told the BBC. “And if that's about half of what we buy, then that means something of the order of five per cent inflation.'

Ian Wright, director general of the Food and Drink Federation, backed up King’s prediction, telling Newsnight that he expected prices to rise next year by 'somewhere between five and eight per cent”.

King told Newsnight one of the high street supermarkets will “for sure” disappear as a result of cost pressures, but declined to predict which one.