Under proposals announced by John Reid, the Home Secretary, about 1,800 skilled and 20,000 unskilled labourers will be given permits to work in the United Kingdom.

But the Government admitted that the new quotas would be difficult to police, as it would be unable to deport illegal workers back to their home countries once they join the EU. The Home Office was unable to say what would happen to an immigrant who failed to pay the fine.

Athough Mr Reid promised unlimited fines on employers found illegally hiring Romanians or Bulgarians, Home Office figures show that, since 2001, only 24 employers have been prosecuted for the offence.

The new system of fines and quotas for low-skilled workers is intended to give teeth to restrictions brought in after public and parliamentary concern at the scale of migration.

Approximately 10,000 new EU immigrants are also expected to come to Britain to work on a self-employed basis.

Mr Reid said that employing illegal workers led to exploitation and would not be tolerated but, privately, Home Office officials admit that the Government faces a huge task in preventing Bulgarians and Romanians travelling to Britain and finding work in the black economy. The Home Secretary told MPs in a written answer: “I must be clear that policing the system against a background of free movement to the UK will present some challenges.

“But workers who are tempted by this into breaking the rules should be aware that they will be robustly enforced.”

Opposition politicans and lawyers gave warning that the measures may prove impossible to police. David Davis, the Shadow Home Secretary, criticised Mr Reid for not making an oral statement in the Commons, so that he could answer questions.

“As a result we were unable to ask him how he will deal with the glaring loopholes in this announcement,” he added.

Nick Clegg, the Liberal Democrat home affairs spokesman, said: “This is asking a lot in terms of enforcement from an Immigration and Nationality Directorate which Mr Reid has branded unfit for purpose.”

THE CURBS

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