Charles Clarke says he was "angry and frustrated" after being sacked as home secretary, adding that he felt Tony Blair had taken "a wrong decision".
He tells the BBC his successor, John Reid, is wrong to say the Home Office is "not fit for purpose" and warns him not to jump on media "bandwagons".
He says he will not take responsibility for all subsequent Home Office crises.
Interviewed by the Times, he says Mr Blair has "lost his sense of purpose" and needs to recover his leadership.
Mr Clarke says he has decided to speak out in a series of interviews to restore his political reputation following his departure in the reshuffle - and to put his "point of view on the record".
He was sacked by Tony Blair in May after it emerged that over seven years, some 1,023 foreign prisoners were released from UK prisons when they should have been considered for deportation.
Mr Clarke tells the BBC he felt the decision to get rid of him was for political expediency rather than long-term reform and had destroyed his chances of carrying through his planned shake-up of the Home Office.
And he says it would not matter to him if he never returned to frontline politics.
In a separate interview with the Times he says that while he hopes Mr Blair will stay on as Labour leader, he needed to "refocus" and recover "the reforming leadership and style which was his great strength over the first seven or eight years of his premiership".
"I do think there is a sense of Tony having lost his sense of purpose and direction, so my advice to him is to recover that sense of purpose and direction".
He praises Gordon Brown - seen almost certainly as Mr Blair's successor - for the way he has prepared for that transition and admits that he advised him to make a number of speeches outside his Treasury brief to help people understand his aims and ambitions for Britain.
In his interview with BBC's Newsnight, Mr Clarke says of all the regrets he has about his departure from the Home Office, the biggest one is not being able to carry out the "massive reforms" needed to the department.
Following his appointment in 2005, Mr Blair had agreed with him that it would take between two and four years "to make the changes which were necessary".
Mr Clarke says after he was told by the prime minister that he was no longer needed as home secretary, he retorted: "'Well I'm not ready to take another job'.
"He did offer me other jobs - I'm not going into the detail, but he did, and I felt I shouldn't accept them because I had pledged myself to myself first of all, but also to the Parliament and to the country that I would resolve this problem."
Asked if he had felt angry with Mr Blair, Mr Clarke replied: "I felt angry with the situation - I didn't feel particularly angry with him as such, even though I thought he took a wrong decision.
"I was angry and frustrated because I felt that this massive task, a great privilege to be asked to be home secretary at the general election, needed to be carried through over a three to four year period and I believed I could do that.
"I believe I should do that and I wanted the chance and opportunity to do that, and so yes, I was angry and frustrated when that chance was removed."
He did not believe Mr Blair had caved into a media campaign, but pressed to say if he thought the decision to let him go was for political expediency, he said: "That's a criticism I would make.
"I think there is some truth in that."
Mr Clarke was asked if he agreed with Mr Reid's assessment that the Home Office was "not fit for purpose", to which he responded: "No, I didn't - I thought that was absolutely not the case... I think John was wrong to say that."
He said he was not hurt by the description. "I think he came in, as every incoming secretary of state is entitled to do and said it as he saw it."
Mr Clarke also appeared scathing about Mr Reid's decision to consider introducing a Megan's Law system for dealing with sex offenders in the UK, following the News of the World campaign.
He said if that decision had been influenced by the paper's campaign "then I would criticise it".
"I don't think that's the right thing to do ... The home secretary of the day should not simply be running on the band wagon of some particular media campaign."
He also says he regrets Mr Reid's decision to delay his carefully structured plans for police mergers.
"I think it's wrong to delay it. I think we've got a timetable which was the right thing to do and I don't agree with his decision in that area."
Shadow home secretary David Davis described Mr Clarke's comments as "the most uncoded attack" he had ever seen by "one ex-minister on his successor".