Chelsea are under investigation for the second time in eight years over a potential breach of Fifa regulations on youth players.

The governing body confirmed on Tuesday it had launched an inquiry into the club’s conduct involving signing foreigners under the age of 18.

Chelsea overturned a transfer ban imposed in 2009 over their 2007 recruitment of Gaël Kakuta from Lens, while last year saw pictures emerge of Bertrand Traoré playing for them before he had international clearance.

A Fifa spokesman said: “As the investigation is ongoing, no further comment is possible for the time being.”

Atlético Madrid are currently under a transfer embargo for breaching rules over the signing of minors, a decision that was upheld on appeal to the Court of Arbitration for Sport.