France defender William Gallas is likely to be punished by Chelsea after failing to join up with the squad on their pre-season tour of the United States.

"William requested extra time off following the World Cup but was informed he should still report to Los Angeles on the date previously agreed with him," read a statement issued by the English champions on Tuesday.

"He did not report and further action will now be considered by the club as a consequence.

"Pre-season training and the tour is about building team spirit among our squad and extra leave is only granted for valid football-related reasons."

Gallas, 28, has struggled to hold down a place in his favoured position of centre back in the Chelsea team and said in May that he wished to leave the London club.

Regarding his future, Chelsea said on Tuesday: "Discussions between Chelsea and William about a new contract are already well documented and ongoing.

"He has one year left on his current contract."

Gallas, who can also play at full back, joined Chelsea from Olympique Marseille for 6.2 million pounds in 2001. He played in France's World Cup final defeat by Italy last month.