Small businesses are leaving themselves open to the threat of legal action and fines by failing to properly police new recruits.

With the Immigration, Ayslum and Nationality Act 2006 now law, the penalties for employing an illegal worker have increased and the onus has been shifted onto business owners to ensure compliance.

But a survey by BusinessZone.co.uk and HRZone.co.uk found that 34% of small businesses currently have no process in place at all to check on the legality of workers, while even in larger businesses 37% leave such enquiries until the candidate has actually accepted a job offer.

"It is a real concern that such a high proportion of businesses do not have a consistent policy in place to verify the legality of their workers, particularly given the consequences of non-compliance," said Laura Mitchell, a solicitor at Clarion Solicitors.

The new legislation will set an even stricter regime for employing overseas workers and it is essential that employers take steps as soon as possible to prepare for the forthcoming changes

"The new legislation will set an even stricter regime for employing overseas workers and it is essential that employers take steps as soon as possible to prepare for the forthcoming changes.

"Implementing and following a clear written procedure based on the requirements of the 2006 Act will provide employers with greater protection against the civil and criminal penalties. Employers who fail to check the legality of their workers do so at their own risk."

Firms can now expect to face a fine of £10,000 for each worker they employ who should not be in the UK, and employers will have to carry out further checks at specified intervals to confirm employees' ongoing right to work.

Those found guilty of employing illegal migrant workers will also receive a criminal record and could face up to two years in jail.

Employers will, however, have a defence if they can prove that it saw, copied and retained copies of original specified documents before employing an individual.