The Safer Travel at Night campaign began in October 2002

From 1 December, taxi touting will become a recordable offence, the Home Office has said.

The move comes as new figures from the Mayor of London suggest a safety campaign has helped reduce the number of sex attacks involving illegal cabs.

There were 155 such attacks in the past year, compared to 212 the year before.

Ministers said recording the DNA and fingerprint details of those arrested would also help track down drivers who continued to flout the law and moved between towns and cities.

Unlicensed drivers are often uninsured and may not even have a British driving licence and many have previous criminal convictions.

It's still vital that we rid London of illegal taxi touts to eradicate this threat to Londoners' safety Ken Livingstone, Mayor of London

Home Office minister Hazel Blears said: "Unlicensed minicab drivers are a menace to the public, particularly women.

"By making taxi touting a recordable offence, the government is giving the police vital new powers to deal with these dangerous individuals."

London's mayor Ken Livingstone has welcomed figures which he says show a drop in the number of sexual assaults against women using illegal cabs since the launch of a Safer Travel at Night campaign a year ago.

There were 212 sexual assaults, including 54 rapes, last year, but those fell to 155 sexual offences, including 42 rapes, this year.

'Think ahead' message

He said new initiatives and campaigns would continue to carry the message during the second year, particularly during the Christmas party season.

"I have worked very hard with the police, Transport for London and other authorities over the last year on getting the safer travel at night message across," Mr Livingstone said.

"It's still vital that we rid London of illegal taxi touts to eradicate this threat to Londoners' safety and keep improving late night travel, including increased bus services."

The Metropolitan Police said the message was to think ahead and either pre-book a licensed minicab, use a black cab or nominate a driver who will not drink.