Gordon Brown’s slogan “British jobs for British workers” amounts to “employment apartheid”, a senior Labour MP said last night.

Keith Vaz, chairman of the Home Affairs Select Committee, said that Britain’s treaty obligations meant the pledge could not be met and that it was “a false attempt to answer to right-wing propaganda”.

Mr Vaz, a former Europe Minister, set out his criticisms during a Commons debate on immigration policy. “I worry about this statement,” he said. “It lacks credible arguments and some have suggested that it appears to amount to little more than employment apartheid.

“It assumes that foreign workers are somehow stealing jobs from UK workers, an idea for which there is absolutely no evidence.

“It also raises the question — how do you ensure jobs are going to British people and what do you classify as British?”

Mr Vaz continued: “Hopes are falsely raised whenever ‘British jobs’ are mentioned. Every position that is filled will require justification and an account kept of how many British jobs there are.

“The fact is, this country has, over the last century, entered many agreements with European and Commonwealth countries, which means that it is obligated, and rightly so, to give jobs to people that are not British, based on merit.”

Mr Vaz said that he was horrified at the “rise in racist comments about eastern Europeans”, adding: “I am concerned that ideas such as ‘British jobs for British people’ may only serve to worsen this situation.”

Earlier, during the debate on the Queen’s Speech. Mr Brown came under fierce attack from David Cameron over the slogan.

The Conservative leader said that the Prime Minister knew the promise to be illegal under European Union law and, brandishing a number of leaflets, added: “I did a bit more research to find out where he got his slogans from.

“Here’s one he borrowed off the National Front. Here’s another one he borrowed off the British National Party. Where was his moral compass when he was doing that?”

The Conservatives later circulated two examples of BNP campaign literature, one from as recently as last year, which used the slogan prominently.

Mr Brown referred to British jobs for British workers in his speech to the Labour conference in Bournemouth in September, and the slogan has been a source of growing embarrassment ever since.

Ministers have had to make a series of embarrassing admissions that the number of migrant workers has been underestimated by as much as 700,000 in recent days. In an attempt to regain the initiative Liam Byrne, the Immigration Minister, last week announced that restrictions on low-skilled would-be migrants from Romania and Bulgaria would remain in place.

That decision has infuriated Mr Vaz, however, who has now invited the Romanian Government to give evidence to the Home Affairs Select Committee later this month.

Mr Vaz pointed out that about 800,000 Britons were working abroad, only 300,000 fewer than the estimated 1.1 million migrants employed in this country.

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