The UK's best-selling car, the Ford Focus, has been hit by claims of handbrake problems, in the wake of concern that the flagship Mondeo was suffering a similar fault.

Ford issued an advice letter to Mondeo drivers denying there were any problems with the car's design, after claims that the cars had moved while parked.

Heather Loveday, fleet manager of Cope and Timmins, a soft furnishings company, is contacting Ford following three similar incidents with drivers of the Focus. She believes her fleet's problems could be linked to those of the Mondeo. The first incident took place in March, prompting warnings to drivers on the 28-car fleet, although two further incidents took place. Since the incidents, all Cope and Timmins Ford Focus drivers have been advised to leave the car in gear while parked.

Ford has denied there has been a problem with the Focus, but said it would investigate the incidents experienced by the Cope and Timmins cars.

A Ford spokesman said: "We are not aware of any problems with the Focus handbrake. Our advice to Mondeo drivers was issued after some reports in the UK and Germany of the Mondeo moving while parked.

"We investigated each incident and there was no common link or cause, so we sent out the advisory letter reminding customers of the procedure because everyone learns to apply the handbrake in different ways."