Tour de France champion Alberto Contador has not ruled out the possibility of being a teammate of Lance Armstrong again despite their difficult relationship when both were with Astana.

Seven-time Tour winner Armstrong has formed a new team, RadioShack, for next season while Spaniard Contador will remain with Kazakh-funded Astana in 2010, despite threatening to leave and opening negotiations with several other leading teams.

Contador and Armstrong clashed over the role of team leader at Astana during this year's Tour de France. However, Contador said on Friday he had put their differences behind him.

"I want to think about sport, I'm not interested in polemics. For me 2009 is finished. Now I want to think about training for my own goals," Contador, in Italy for an Astana training camp, told a news conference.

"Things were difficult during the Tour de France and it was very stressful but it was also good experience for the future. I matured a lot and learnt to stay cool.

"It's possible that I could be friends or an ally with Lance in the future. In sport you can never say never."

Contador said his only focus this year would be on the Tour de France because of the lack of experienced riders at Astana following Armstrong's departure, although Spain's 2006 Tour de France winner Oscar Pereiro signed a one-year deal earlier this week.

"This team hasn't many big names but we need to see the team on the road before saying anything. I hope we'll have a strong team for the Tour de France," he said.

"In 2010 I can't think about riding two major stage races, so that's why the Tour de France is my big goal."

Alexander Vinokourov of Kazakhstan has returned to the Astana team after serving a two-year ban for blood doping but he and Contador will ride separate race programmes until July.