Madrid - Former Tour de France champion Alberto Contador underwent surgery to relieve a blockage in his nasal passage and to remove a polyp on his vocal cord on Monday.

Contador said the operation would force him to miss a December training camp of his Astana team in Tenerife even though he will travel to the island for light training in the gym.

"The moment to take the bike again will depend of how I evolve, but I have thought to use the stage in Tenerife to make a specific work in the gym," he said on his website.

Contador said the operation and recovery won't seriously hamper his preparation for the 2009 season which he plans to start as planned with the Tour of Valencia February 24-28.

"Perhaps I'll be delayed a couple of weeks the preparation, but that doesn't have a lot of importance ... I have been on rest to recover of the so loaded season that I have had. I have time to begin well in my first race that will probably be the Vuelta a Valencia," he said.

Contador won the Tour in 2007 and added the Giro d'Italia and Vuelta crowns in 2008 for a title treble of the biggest stage races. He couldn't compete at the Tour this year because Astana were not invited due to its doping-tainted past.

Contador will be joined at Astana in 2009 by seven-time Tour champion Lance Armstrong who has come out of retirement. (dpa)