The BBC's Paul Welsh: "The only defence is to switch on the wipers"

Squeegee gangs are a familiar sight in many cities. Armed with a buckets and sponges they demand payment for cleaning a windscreen, whether invited to do so or not.

But now Westminster City Council has announced it will be using new powers under the Crime and Disorder Act in an attempt to rid its streets of the gangs.

A team of 12 inspectors and police will enforce a clampdown that has been prompted by complaints.

The big squeeze: Police move in at the lights

Assertive drivers defend against the impromptu spongings by inching forward at the lights, or turning on their windscreen wipers.

But for some, the experience can be an intimidating one.

Westminster councillor Melvyn Caplan said: "We have had an increasing number of complaints of aggressive groups of people, not just one person or two people but several people jumping out in front of motorists.

"One perhaps doing the actual work on the windscreen and two or three others collecting money, often with menaces."

Previously squeegee offenders were prosecuted for trading without a licence.