Gallas recently joined Arsenal after several months of stating his desire to leave to manager Jose Mourinho.

And only days after he moved across London in a deal which also took Arsenal defender Ashley Cole the other way, a Chelsea statement claims to lay bare the extent to which Gallas would have gone if not granted his wish to leave.

Chelsea claim Gallas initially refused to play against Liverpool in last season's FA Cup semi-final and how, if selected to play against Manchester City in the first game of this season, he threatened to score an own goal, get sent off or make deliberate mistakes.

The statement read: "Chelsea believes it is important for our supporters to be made aware of the full facts regarding William Gallas and the lack of respect he showed to the fans, the manager and the club.

"Despite leaving he continues to attack Jose Mourinho and this cannot be left unchallenged.

"Chelsea made William Gallas a very substantial and attractive new contract offer to stay towards the end of last season. This was rejected.

"The issue was purely one of money, despite his public comments that he wanted a new challenge, to play abroad and so forth. These were just a smokescreen to cover up the fact he was hawking himself to the highest bidder.

"Having failed to secure his demands, his position became increasingly intransigent and unacceptable.

"He initially refused to play against Liverpool in the FA Cup semi-final last season in an effort to force an increased contract offer.

"As is now well-documented he refused to join up with the team in Los Angeles during pre-season, despite agreeing the dates for his return as the other World Cup players did, with the club."

The statement continued: "Before the first game of the season against Manchester City, when only four defenders were available and John Terry was doubtful with an injury, he refused to play.

"He went on to threaten that if he was forced to play, or if he was disciplined and financially punished for his breach of the rules, that he could score an own goal or get himself sent off, or make deliberate mistakes.

"Clearly this was a totally unacceptable situation for the manager, the team and the club. So a collectively-agreed solution in Chelsea's interests had to be found, hence his departure."

However Gallas, who is away on international duty with France for whom he starred at the World Cup reaching the final where they lost the final on penalties to Italy, hit back.

"I am surprised and shocked by these claims," the 29-year-old told AFP.

"I never said that I would score own goals if I had to play for Chelsea again.

"I was firm about my wanting to leave, that is true, and I will explain in due time why I wanted to.

"But I never went that far.

"But if people want to hide behind false accusations in order to give a reason for why I left so they can calm down the club's supporters then they can," added Gallas, who played 225 matches for Chelsea and was an integral part of their two Premiership winning sides.

Much of Chelsea's statement will explain why Mourinho called on the player to make public the reasons why he was not being considered for selection by the club.

Mourinho asked the player to hold a press conference before he was sold to Arsenal on deadline day.

Gallas, a six million pounds signing from Marseille five years ago, has been keen to leave since May as he was believed to be annoyed at having to play at fullback instead of his preferred centre back position which was the rpeserve of England captain John Terry and Portuguese international Ricardo Carvalho.

Gallas provoked a wider rift in August when he failed to arrive on time for their tour of the United States and was told not to bother turning up atall.

Chelsea manager Jose Mourinho condemned the player's "lack of respect" and stripped him of his number 13 shirt, giving it to newcomer Michael Ballack, who had originally been give the No 19 shirt.