Next year's Tour finishes on July 22, less than a fortnight before the Olympic track qualifiers begin, so Thomas plans instead to take part in the Giro d'Italia, which will give him the opportunity of winning another gold to go with the one he took in the team pursuit at the 2008 Beijing Games.

"The Olympics is the main goal for me so I don't want to jeopardise that in anyway," he told BBC Sport Wales.

"Riding the tour is a bit more of a gamble.

"I could be going really [well] but could also end up on my knees and pretty tired.

"I'm going to be doing similar preparations to before Beijing when I rode the Giro and didn't ride the tour.

"That'll give me the work from a three-week race but also give me time to adapt back to the track and give myself every chance of making the team."

The 25-year-old from Cardiff said the decision to pull out of the Tour was his decision alone.

"It was down to me at the end of the day," said Thomas, who has hinted that London 2012 may be his last track cycling event.

"I obviously spoke to the coaches and staff but it was my call and I'm pretty comfortable with that.

"It [the Tour de France] is massive, and especially next year with Cav [Mark Cavendish] on the team I'd love to be a part of it.

"But for me this year, as in previous years, the Olympics is the main goal.

"I'll still have the Tour de France the year after, it's an annual event so that's one way we're fortunate.

"But home Olympics, it's a once in a lifetime thing."

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