Tour de France champion Alberto Contador will not be invited back to this year's race after his Astana team were excluded from the 2008 edition, race organisers announced.

The Kazakh funded team was at the centre of a doping controversy at last year's Grande Boucle after team leader Alexandre Vinokourov tested positive for blood-doping and was subsequently banned from the race.

Amaury Sport Organisation officials attributed their decision to exclude the team from all events organised this year, including the Tour, to "the damage caused by this team to the Tour de France and to cycling in general in 2006 and in 2007."

"The Astana team essentially betrayed, last year, the confidence of race organisers who invited them in good faith," ASO organisers said in a statement.

"ASO will continue to pay attention to the efforts that Astana implements to participate in a 2008 season without affairs or suspicion, and could then consider them for possible participation in future races."

"Astana have appointed a new leadership and their manager Johan Bruyneel has asked us to trust them but we can't," Tour Director Christian Prudhomme told Reuters.

Astana took over from the Spanish Liberty Seguros squad that was left out of the 2006 Tour after several of their riders were barred because of alleged implication in the Operacion Puerto doping probe.

"We remember what happened in 2006," said Prudhomme. "Then came 2007 with a new team who asked us to trust them. We did that and paid dearly for it."

Contador, riding in the fourth stage of the Mallorca Challenge, broke clear at the front of the race on Wednesday and drew close to the television crew car, shouting "Astana for the Tour, Astana for the Tour," before being chased down by the peloton four kilometres from the finish line.

"My aim this year was to win it again, but they've deprived me of that opportunity. Astana should be in the Tour," Contador said after finishing the race.

"The Tour is the race I've always dreamed about, I've always fought for it and I hope I'll still be fighting for it in the future."

The team also includes 2007 Tour podium finisher Levi Leipheimer and 2006 second-place finisher Andreas Kloeden, who will also both be barred from this year's race.

The ASO's decision follows a similar verdict to ban Astana by organisers of the year's first Grand Tour, the Giro D'Italia.

Contador, who won the scandal-plagued 2007 edition of the biggest race in cycling, had earlier said that he expected his team to be included in this year's race.

"I don't believe I will not race the Tour de France," the Spaniard said at the time.

"I think the Giro organisers' decision has been blown way out of proportion. It's a different race, not on the same level as the Tour de France."

The list of teams invited on the Tour will be announced on February 29.

Jeremy Stahl / Eurosport