Beijing - The president of football's governing body FIFA, Joseph Blatter, on Monday made an impassioned plea to European clubs to allow all under-23 players to participate at the Olympics.

The men's Olympic football tournament that starts on August 7, a day ahead of the official opening of the Beijing Olympics, is open to under-23 players, but three clubs have appealed to the Court of Arbitration for Sport (CAS) for the return of their players who are already in China.

German clubs Werder Bremen and Schalke 04, as well as Barcelona, have approached CAS about their players Diego, Rafinha and Lionel Messi, respectively.

Blatter told a news conference that whatever the outcome before the world's highest sports arbitration body, due in the next two days, FIFA would say to the players they should stay and play.

"We are bound by the decisions of CAS, but even if it is a decision that is negative for the players, I would say: Let them play."

He said that he would hope that should CAS rule in favour of the three clubs, the clubs would allow the players to stay.

"The clubs should then say: We were right to appeal to CAS, but in the spirit of the Olympic Games we will let them stay and play," said Blatter. (dpa)