Charles Clarke has defended his actions as the home secretary at the heart of the foreign prisoners scandal.

In his first comments since leaving his post as home secretary over the affair last month, Clarke conceded he was "probably responsible" for some of the confusion in the media over numbers of foreign prisoners.

However he said the suggestion that he had known the extent of the problem of prisoners not being considered for deportation and not done anything about it was wrong.

Clarke defended his position in a letter to the Commons home affairs select committee, which is investigating the scandal.

In a detailed outline of events leading up to him being sacked by Tony Blair, he insisted that it was not until March 17 this year that ministers were made aware of the "specific problem" involving 1,019 foreign prisoners being freed without being considered for deportation.

And he said he only received a more detailed briefing on the scale of the problem on March 31.

"The suggestion that from July 2005 I had personally known about the failure to consider deportation and done nothing about it was wrong," Clarke said.

"It was only in late March that ministers, including myself, were made aware of the failure to consider for deportation some foreign national prisoners at the end of their sentence, and when we were made aware of this action was then taken."

But he added: "Looking back, I am sure that it would have been better of the operational process to pursue these foreign national prisoners had been commenced earlier - at least upon receipt of the March 31 submission.

"Given the history of this matter, however, I felt at the time it was important to make sure that the information was as accurate as possible before it was reported to the House, and then to the public and the media."

Former Home Office minister Fiona Mactaggart, who also left the government in the May reshuffle, defended Clarke's decision to "set the record straight".

And speaking to BBC Radio 4's World at One, she also said she believed he had been treated unfairly.

"I do think that he wasn't treated fairly but I understand it's the prime minister's right to make those sorts of decisions," she said.

"But I also think it is Charles Clarke's right to say: 'This is actually the record and you can judge me on that.'"