PARIS (AFP) - World governing body Fifa insisted Friday that Hatem Ben Arfa has already played for two clubs this season and his transfer from Newcastle to Nice, therefore, cannot be validated.

The 27-year-old French star had turned out for Newcastle's under-21 team at the beginning of the season and also played for Premier League side Hull on loan.

Under Fifa rules, he cannot join a third team during the same season.

"We can confirm that the decision was notified to the French Football Federation following a request for clarification," said a Fifa spokesman.

"This decision stipulates that matches in the English Under-21 championship are considered to be official matches under Fifa rules."

The French Football League immediately slapped a ban on Ben Arfa from playing for Nice this season.

However, the league's judicial commission said they would allow the player to train with the Ligue 1 club.

The English Football Association (FA) had contacted Fifa on Jan 23 in a bid to clear up confusion concerning the transfer of the French international midfielder.

"We don't consider U21 games as official matches," the FA said in letter to Fifa, in a bid to "clear all ambiguity" concerning Ben Arfa's case.