A lawyer for Hugh Grant has criticised the Mail on Sunday after the paper accused the actor of making "mendacious smears" in his evidence to the Leveson Inquiry.
The Four Weddings And A Funeral star suggested on Monday that the paper hacked his phone before printing a "bizarre" article in February 2007 about his relationship with then-girlfriend Jemima Khan.
"I cannot for the life of me think of any conceivable source for this story in the Mail on Sunday except those voice messages on my mobile telephone," he told the inquiry into press standards.
The Mail on Sunday later issued a strongly-worded statement saying it "utterly refuted" Grant's claim that it got any story as a result of phone hacking.
The statement - which was reported by media outlets including the Sunday title's sister paper the Daily Mail - concluded: "Mr Grant's allegations are mendacious smears driven by his hatred of the media."
David Sherborne, counsel for Grant and 50 other alleged victims of press intrusion, told the inquiry yesterday that this statement was "an allegation of the most serious kind" against the actor.
"What was filed, so to speak, in the pages of the Daily Mail website and the Daily Mail itself, was not a denial but a personal attack on Mr Grant as a witness, in which they referred to his inference not as a mistake, not even wrong, but as a 'mendacious smear' from a man 'driven by hatred of the media'," he said.
Jonathan Caplan QC, counsel for Associated Newspapers, publishers of the Daily Mail and the Mail on Sunday, said the newspaper had wanted to respond to the actor's serious claims.
He said: "Mr Grant is entitled to comment as he wishes. But we sought to make the point that that comment was based on the flimsiest of material and his allegation that the journalists of Associated Newspapers had been involved in phone hacking was utterly refuted.
"That allegation is extremely serious. It is an allegation of criminal conduct."
Inquiry chairman Lord Justice Leveson said he considered it would be "fine" for Associated Newspapers to issue a factual denial of allegations made against the company's titles.
"The real issue is the extent to which it is appropriate to go from the defensive onto the offensive in that way," he told the hearing.