French defender William Gallas has accused Chelsea of 'hiding behind false accusations' after being stunned by his former club's claim that he threatened to score an own goal.
Gallas, who joined Arsenal on deadline day in a cash-plus-player deal that saw England left-back Ashley Cole move in the opposite direction, denied making the threat and said the Barclays Premiership champions 'lacked class'.
The French defender, currently preparing for his country's Euro 2008 qualifier against Italy, revealed he would explain his reasons for quitting Stamford Bridge at an 'appropriate' time.
Gallas was forced to respond after Chelsea, in an unprecedented move, issued a statement which alleged Gallas refused to play against Liverpool in last season's FA Cup semi-final and against Manchester City at the beginning of the current campaign.
The club insisted that he threatened to score an own goal, get himself sent-off or make deliberate mistakes if Mourinho picked him for the home clash against City.
But Gallas declared: 'I am surprised and shocked by these remarks.
'I never said that I would score an own goal. I was very firm in my will to leave, that is clear, and I will explain at the appropriate time why.
'If people want to hide behind these eccentric charges to explain my departure instead of assuming their responsibilities in front of their supporters, then they can do.
'All this is very, very petty on behalf of Chelsea. But at the same time, coming on behalf of its new leaders, that does not surprise me. Even if Chelsea has much money, its new leaders lack class.'
Meanwhile, Chelsea have accused the French Football Federation of prolonging a row over Claude Makelele's international selection by deliberately inflaming a situation that is set to be resolved.
The Premiership champions came under renewed criticism from France coach Raymond Domenech and defender Lilian Thuram after Mourinho had accused Domenech of treating Makelele like a `slave' for not allowing him to quit international football.
Chelsea claim Domenech did not understand Mourinho's use of the word as a metaphor to highlight Makelele's situation.
A Chelsea statement read: 'Ill-considered comments regarding Claude Makelele's international career continue to come from the French camp, in particular Lilian Thuram, and the French national team coach, Raymond Domenech.
'Thuram and Domenech fail to understand Josi Mourinho's comments regarding `slavery' which were purely a metaphor to illustrate the Makelele problem, a figure of speech rather than a literal comparison with slavery as a social and political issue.
'As a result of their failings, deliberately inflammatory comments will only cloud a problem which is on its way to being resolved.'
Makelele had informed the FFF federation he wanted to retire from international duty after their World Cup final defeat by Italy.
This decision was reinforced by a letter to the FFF which was faxed to their HQ on August 22 - two days prior to his latest call-up.
However, Domenech threatened to have Makelele suspended for up to four domestic games by world governing body FIFA if he failed to join up with his international team-mates.
Chelsea now hope that Makelele will be allowed to retire after their Euro 2008 qualifier against Italy which the midfielder may miss after suffering an injury in the 3-0 win over Georgia on Saturday.