Video: PMQs: David Cameron forced to defend tax credit cuts David Cameron was today forced to defend the Government's plan to make parents work longer before they can receive tax credits. The Prime Minister said the move to increase the weekly hours requirement to qualify from 16 to 24 hours for couples was fair, but Ed Miliband accused him of breaking promises. Speaking at Prime Minister Questions in the Commons, Mr Cameron said: "We are dealing with a basic unfairness where we ask a single parent to work 16 hours before getting access to the tax credit system, so it's only right to say to couples that between them they should work 24 hours - ie, 12 hours each." Ed Miliband pointed out that in the run-up to the May 2010 General Election, Mr Cameron said Labour's claim that the Conservatives' plan to reform tax credits would hit low-income families was "simply not true." Mr Miliband asked him: "Why have you broken that promise?" But Mr Cameron hit back, blaming the "massive" budget deficit for the need to revamp the system and denied the change was "unreasonable." The Labour leader said many families unable to find extra work would be better off on benefits if the tax changes go through.