Contador has had three very successful seasons with Astana
Tour de France winner Alberto Contador will leave Astana at the end of this season after the Spaniard rejected the team's offer to extend his contract.
A representative of Contador said: "The position of both parties was not so far from each other, but the team wanted to know whether [he would renew his deal].
"Alberto Contador has rejected the ultimatum of Astana."
In three seasons with Astana, Contador, 27, won two of his three Tour titles, a Giro d'Italia and Spanish Vuelta title.
Contador said in a statement that he "will calmly study all of the possibilities on offer for the coming season", adding that "he hasn't dismissed any of them".
However, he did not divulge the offers he was considering.
Contador joined Astana in 2008 after the Discovery Channel team was disbanded following the Pinto-born rider's Tour triumph in 2007.
He went on to win the Tour with them in 2009 and successfully defended his title this year - albeit without managing a stage win and, by his own admission, failing to hit his best form.
Contador also said that he felt "our team perhaps wasn't the strongest", although he did pay tribute to Astana's togetherness.
The Spaniard arrived at Astana alongside team boss Johan Bruyneel in 2008, on the heels of his first Tour victory with the Discovery Channel team.
But Tour organisers denied Astana a place in the race that year because of doping violations.
Instead, Contador became only the fifth cyclist to win all three of cycling's premier events with Giro and Vuelta triumphs - and the fastest to accomplish the feat.
Contador overcame the return of seven-time Tour champion Lance Armstrong with Astana last year year to win cycling's classic event for the second time before taking his third Tour title on Sunday.
Kazakhstan-based Astana struggled to pay wages last year, and Bruyneel left the team at the end of last season alongside Armstrong.