The Government is facing fresh questions over the number of foreign workers in Britain.

Home Secretary Jacqui Smith said she was "sorry" the Government got its figures wrong about the increase in foreign nationals since 1997, after it emerged 300,000 migrant workers were missed out of official figures.

Nearly a third of the 1.1 million arrivals were missed out of the original figures. This means 40.7 per cent of the 2.7 million jobs created since Labour came to power have gone to foreigners.

The Tories have now dug out a parliamentary answer by the National Statistician from July.

In it, Karen Dunnell said: "For the three-month period ending March 2007 there were 1.5 million overseas born people in employment who had entered the UK in the last ten years."

But the Department for Work and Pensions has rejected any suggestion that it was revising its statistics again, insisting that the new figure was not comparing like with like.

A spokesman for the department said: "The Parliamentary answer relates to workers born overseas and there are 1.1 million foreign nationals working in the UK.

"The remaining 400,000 are people who were born overseas but are UK citizens, they are not foreign nationals."

Shadow pensions secretary Chris Grayling said: "This situation just gets worse; it's clear we simply can't trust the figures or statements put out by the Government on migrant workers in the UK."

Gordon Brown has sought to dampen down the row, insisting the Government is taking steps to tighten up the system.

The Prime Minister outlined measures including an Australian-style points-based system for people coming in from outside the EU, ID cards for foreign nationals and counting people in and out of the country.

He added that the Government announced on Tuesday that restrictions would remain in force on Romanians and Bulgarians who want to work in Britain.

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