Proposals to appoint a "commissar" to ensure working class access to universities have been attacked by the Conservatives.

Ahead of a white paper on university funding, Charles Clarke has confirmed plans to appoint an "access regulator".

The education secretary's move follows concerns that increased top-up fees at the country's elite universities could see the emergence of a "two tier" system.

A new watchdog, branded a Soviet-style "political commissar" by some academics, would ensure universities meet obligations to meet access quotas for those from disadvantaged backgrounds.

The shadow education secretary, Damian Green, thinks the plan could threaten academic freedom.

"I think the idea of a government-appointed regulator, to tell universities who they can and can't take, is disgraceful," he told GMTV's Sunday Programme.

"It cuts away at academic freedom."

Green also believes such "social engineering" will lead to unfairness.

"It will mean that there will be children who work hard for their A Levels expecting to get to university, and are then told by this government regulator, 'sorry - your face doesn't fit'," he said.

"That is social engineering of the worst kind."

In an interview with BBC1's Breakfast with Frost, Clarke rejected accusations that regulation amounted to political interference.

"No regulator will be a political commissar," he insisted."Although the system has been a success over recent years in expanding, it hasn't been a success in recent years in getting people from poorer backgrounds to be able to go to university and they know that they have got to do that."

Conservatives will argue, however, that the government should scrap an "arbitrary" target to get half the country's school leavers into university.

"I think it's arbitrary, and I think it's not good educationally," said Green.

"The target was plucked out of thin air."

"I suspect that in his heart of hearts, Charles Clarke knows it's a nonsensical target - but he hasn't actually got the guts to drop it publicly."