Families whose desperation to find an affordable nanny leads them to hire an illegal immigrant face fines of up to £2,000 or a two-year jail sentence.

A concerted drive to tackle the booming black market for foreign bar and restaurant staff, shopworkers and builders, as well as for child-carers, was announced by the Government yesterday. Although it is primarily aimed at gangmasters and shady employment agencies, the move could also hit householders who take on non-EU nannies, au pairs and cleaners without checking their immigration status.