Forwards Dirk Nowitzki of the Dallas Mavericks and Amare Stoudemire of the New York Knicks will not play for Germany and the United States, respectively, at next month's world championship in Turkey.

The German basketball federation said Tuesday that Nowitzki, a nine-time NBA all-star, would be back for the 2011 European Championship that will also serve as a qualifying tournament for the 2012 Olympics in London.

"Next summer I'd like to try with the team to make our common goal of playing at the Olympics," Nowitzki said in a statement published by the federation.

The announcement came shortly after the Mavericks signed the 32-year-old Nowitzki to a new contract, a deal reportedly worth over $80 million US for four years.

"I signed a new contract in Dallas, where there are new conditions with a new team and I'd like to concentrate 100 per cent this summer on the upcoming NBA season," the German federation quoted Nowitzki as saying.

The 12-year NBA veteran was the league's MVP in 2007. He became the 34th player in league history to reach 20,000 career points on Jan. 13 and ranks 27th among all-time scorers.

Stoudemire won't play because of problems insuring his contract, a damaging blow to the Americans on the day training camp opened.

He was expected to be one of the Americans' top players in Turkey, but the team learned of the change of plans Tuesday.

Knick enjoyed '07 tourney

The Knicks asked Stoudemire to pull out Monday night and he understood, though he was looking forward to rejoining the team after playing for the Americans in the 2007 Olympic qualifying tournament.

ESPN.com first reported that Stoudemire might not be available to play in the championships that begin Aug. 28.

Stoudemire has had microfracture knee surgery among his injuries, a major reason Phoenix wouldn't offer him a maximum length contract. The Knicks then gave him a five-year deal worth nearly $100 million, even while saying they weren't sure if the contract could be insured.

According to the Knicks, the insurance policy from Stoudemire's contract with the Suns is still in place, but it excludes his surgically repaired left knee. The Knicks have begun working to secure insurance on his new deal, but that hasn't been completed.

Without proper insurance, NBA teams can prevent players from taking part in summer events.

With the players who led the Americans to the 2008 Olympic gold medal taking the summer off, USA Basketball was counting on Stoudemire.

Asked about his commitment to playing in the world championships recently while taking questions from the media on Twitter, Stoudemire wrote: "I'm so ready to play for USA. There isn't anything that would stop me for playing for the US."