Armstrong fears Tour ban

"There is a very high likelihood they will prohibit me from riding on the Tour," the 37-year-old American said on his website.

The AFLD had earlier said Armstrong could face disciplinary action because he "did not respect the obligation to stay under (the) direct and permanent observation" of a drugs tester who came to his southern France residence last month.

Armstrong said he went to shower while Astana team manager Johan Bruyneel was checking the tester's credentials with the International Cycling Union.

"He (the tester) was odd, he was alone. He seemed suspicious," said Armstrong.

The Texan, who fought testicular cancer before coming back in 1998, was asked to provide urine, blood and hair samples when returning from a training ride around Beaulieu-sur-Mer last month.

Any sanction imposed on Armstrong would be valid on French territory only.

"It's too bad. The Tour is something I love dearly, something I wanted to ride, to race in, to be competitive in, either go for a victory or help Albert (Contador) or Levi (Leipheimer) get a victory," he said.

"We shall see. The comeback has been important to me for two main reasons.

"Obviously I have a passion for cycling still, but more importantly I have a passion for the global fight against cancer.

"I wanted to tell that story in France but if we can't do that we can't do that it's their call, it's their country, their event, their rules so we have to play by those."

Armstrong has had a difficult relationship with Tour organisers, the Amaury Sport Organisation, who said last year the 37-year-old's return to the race would be "embarrassing".

In 2005, the French sports daily L'Equipe, owned by ASO's parent company Editions Philippe Amaury, claimed samples of Armstrong's urine from the 1999 race showed traces of the banned blood-boosting substance erythropoietin.

However, Armstrong, who has never tested positive, was cleared by a Dutch investigator appointed by UCI.

AFLD president Pierre Bordry last year invited Armstrong to have his 1999 samples re-tested but the Texan declined, arguing they could have been compromised.