David Cameron yesterday faced a furious backlash from teachers after he criticised staff for refusing to play their part in running school sports.

The Prime Minister warned there would have to be a “big cultural change” in schools if Britain was to build a successful sporting legacy in the wake of the London Olympics.

His comments drew an angry response from teaching unions who pointed to cuts to the School Sport Partnership and the continued sell-off of school playing fields, despite coalition promises that they would be protected.

The row erupted as it emerged that ministers had ditched a target introduced by the former Labour government for all state school pupils to take part in at least two hours of PE and sport a week.

Mr Cameron defended the decision, arguing that Labour’s approach had been counter-productive. The Prime Minister insisted a lack of resources was not the problem, with £1 billion being invested in school sport over the next four years, and said the real issue was the need to restore a “competitive ethos”.

He said, “We need a big cultural change – a cultural change in favour of competitive sports. That’s what I think really matters.” His comments were branded “foolhardy” by Christine Blower, general secretary of the National Union of Teachers, who said he failed to realise that he was “the architect of a worsening situation”.

Chris Keates, general secretary of the NASUWT teaching union, said it was “unfair” to blame schools for failing to foster a competitive spirit. “The real issue is the major cuts that this coalition Government has made to school sports. They have cut school budgets in real terms, which has reduced the resources available for schools to spend on sport,” she said.

“By ratcheting up the high stakes school accountability regime, ministers have forced schools to focus on a narrow core of academic subjects, which has reduced time in the curriculum for PE.”