Traction control systems and automatic gearboxes are to be outlawed from Formula One, starting at the British Grand Prix on 20 July.

But drivers will still be able to communicate with their teams, despite an earlier plan for the immediate elimination of pit-to-car radio.

If a race car fails just before the start, any spare car will start from the pit lane FIA

"Traction control and automatic gearboxes will no longer be allowed from the 2003 British Grand Prix," the sport's governing body, the FIA, said in a statement on Monday.

The ruling falls half-way between the FIA's desire to ban "driver aids" from the start of the season on 9 March, and the opposition of some teams to any change until 2004.

In other confirmed changes, pit-to-car telemetry - which allows engineers to change car settings during a race - will be abolished from the start of the season.

The FIA has also relaxed a ruling on spare cars, permitting them to be used if a drivers' race car has been damaged, as long as they start from the pit-lane.

"If a race car fails just before the start, any spare car will start from the pit lane, as will a spare car used following a race stoppage in the first two laps," FIA added.