An independent commission fined West Ham 5.5 million pounds (10.8 million dollars), but several clubs felt they were let off lightly.

FIFA president Sepp Blatter said: "We will look at this. We will ask for the file once it has been decided how and why the decision was made.

"If we feel something was wrong in this decision then we have to open our file."

Several top flight clubs are considering legal action against the Premier League over the commission's sanction, claiming the Hammers should have been deducted points.

Sheffield United, who were relegated on the final day of the season as West Ham survived, are leading the fight against the decision.

Argentine striker Tevez played a key role in West Ham's escape from relegation as he scored seven goals in the club's last 10 games.

Blatter said in terms of timescale a "decision would have to be taken immediately."

He added that according to FIFA's files the transfer of Tevez and Mascherano from Brazilian side Corinthians to West Ham had complied with international transfer regulations.

Blatter added: "We will monitor this situation very carefully and once this situation is dealt with by the league and the (Football Association) FA we will ask for the files and have a look because we have the right and the responsibility to see how such cases are dealt with.

"The matter is linked with a club in Brazil - Corinthians - and with the ownership of this club and the ownership of the two players.

"According to our files the transfer of Tevez was done correctly according to the international transfer of players."

Blatter said a recent ruling by the Swiss federal court against Spanish third division side Rayo Vallecano meant FIFA did have jurisdiction over individual clubs.

He added: "Yes we have the power. The Swiss federal court has made a ruling by saying that FIFA and its associations have the right and the power to use all 14 sanctions of the disciplinary code starting with a warning and ending with exclusion of a member via relegation and deduction of points."

In the Rayo Vallecano case, the Spanish club had been threatened with relegation if it did not pay transfer fees owed to a Brazilian club. It claimed, unsuccessfully, that FIFA did not have the power to do so.