Speaking to journalists during his visit to Afghanistan this morning, Mr Cameron has again stressed that he had wanted to keep Mr Mitchell in his job.
"I think there is a lot of sympathy for Andrew because the revelation about the email... has shocked quite a lot of people," he said. "Some people would have been influenced by that."
He said he had spoken to the Sutton Coldfield MP on Monday.
"I saw him in Number 10. I spoke to him and my office has been in contact with him, as you would expect, fairly regularly," he said.
Asked what frame of mind Mr Mitchell was in, the premier replied:
"I thought his mood was very calm and rational given what were very disturbing revelations."
A report out today says David Cameron brought in the the wrong person to investigate 'Plebgate'.
Andrew Mitchell has written a piece in which he has accused the police of trying to destroy his career in a smear campaign.
A police officer who claimed to have witnessed Andrew Mitchell's 'rant' at Downing Street is being investigated by the police watchdog.