PAU, France, July 24 - French Health and Sports minister Roselyne Bachelot said on Tuesday there could be more positive dope tests on this year's Tour de France.

"I want to fight doping with utter determination," Bachelot told French Radio France Info.

"We cannot exclude that during this week, other tests return positive."

Kazakh rider Alexander Vinokourov tested positive for blood-doping after Saturday's time trial on the Tour and has been sacked by his team Astana.

The Swiss team backed by Kazakh companies pulled out of the race on Tuesday.