The father of British Prime Minister David Cameron has suffered a heart attack while on a holiday in France, a spokesman said.

Ian Cameron, 78, was 'seriously ill', and the prime minister has flown to his father's bedside in France, Sky News Wednesday quoted a Downing Street spokesman as saying.

'After talking to doctors at the hospital, the prime minister has decided to fly to be with his father and mother Mary,' he said.

Deputy Prime Minister Nick Clegg will stand in for Cameron.

Ian Cameron worked as a stockbroker before he retired.