MONACO (AFP) - Seven-time champion Lance Armstrong made his return to the Tour de France on Saturday after completing the opening stage time trial.

After an absence of four years from the race he won between 1999 and 2005, the 37-year-old American clocked a time of 20min 12.36sec for the race against the clock which many believe will be a good indicator of who can win the race.

It gave him the provisional lead with a 30sec advantage on Belgian Maxime Monfort, although most of the favourites for the overall victory had yet to start.

Armstrong, who rides for the same Astana team as yellow jersey favourite Alberto Contador, started 18th from the field of 180 riders, giving the thousands of roadside fans an early glimpse of the action.

Swiss Olympic champion Fabian Cancellara and Contador are among a handful of riders being tipped for the stage victory, and the first yellow jersey of this year's race.

They will all race towards the end at one-and-a-half minute intervals - although weather experts have predicted that some rain may fall on the hilly, technical course.

Defending yellow jersey champion Carlos Sastre is last to start, at eight minutes past seven local time (1808 GMT).