Motorists suspected of driving while on drugs face a tough new challenge from Sussex Police - touching their nose with their eyes shut.

Motorists will also be asked to walk a white line. If they wobble or fail the nose test they could be in line for prosecution.

Both tests are widely used in the USA and are being imported to help detect drugged up drivers, who can't be caught with breath tests.

Field Impairment Testing (FIT), which includes the nose-eyes exercise, has been introduced as part of a campaign to cut road deaths and serious injuries.

But police cannot force drivers to take the test. Sergeant Trevor Botting said: "There has been no change in legislation and we have no new powers.

"The offence of driving or attempting to drive while unfit through drink or drugs requires evidence of impairment and of the cause.

"Until now there has been no standardised test but the FIT uses some of the standard sobriety tests used widely in the USA."

Following the use of a breath test to eliminate alcohol as the probable cause of impairment, officers will carry out FIT, which consists of five tests including the nose-eyes and walk-the-line exercises.

He said: "The results will give a good indication whether impairment exists and the type of drug present.

"The suspect who fails will be arrested and examined by a police surgeon, who may seek a sample for analysis."

Mr Botting said the FIT tests had been audited for compliance with Human Rights legislation.

Sussex Police hope the tests will help bring down the number of road casualties.

In 1999, 93 people were killed and 1063 were seriously injured in the county. The figures fell last year to 91 killed and 985 seriously hurt.

Up to April this year, 30 people had died and 285 had been seriously injured.