Ken Clarke survives after offering clarification

The Cabinet's most experienced minister Kenneth Clarke kept his job last night, but there is growing speculation he will be moved from the Ministry of Justice after provoking outrage by suggesting that some rapes were less serious than others.

The Justice Secretary is also fighting to preserve his proposals to reform the sentencing of criminals. He rejected calls for him to apologise for his insensitive remarks in a radio interview, but he was ordered by Downing Street to launch a damage-limitation exercise in a second round of media interviews in which he insisted that he regarded all rapes as serious crimes.

Mr Clarke's initial comments infuriated David Cameron, who was ambushed over them at Prime Minister's Questions by the Labour leader Ed Miliband, who demanded that the Justice Secretary be sacked. Some allies of Mr Cameron fear that Mr Clarke's "prison isn't working" mantra is alienating natural Conservative supporters who want a "tough" line on crime. Last night Tory MPs stepped up the pressure on Mr Cameron to ditch the "soft" sentencing proposals.

At present, offenders can earn a 33 per cent reduction in their sentence by pleading guilty at an early stage. Mr Clarke wants to raise that "discount" to 50 per cent. He believes that, in rape cases, that would spare more victims the ordeal of appearing in court – as well as cutting police and court costs.

This new policy on plea bargaining has been backed in principle by the Cabinet's Home Affairs Committee. The Liberal Democrats strongly support Mr Clarke's approach to criminal justice.

But Downing Street insisted that no final decision has been taken about the sentencing plans due to be unveiled shortly. Yesterday's controversy could persuade Mr Cameron to demand a rethink. Some Liberal Democrats fear the new sentencing policy could now be in jeopardy. "It would be a shame if a sensible approach was blown off course by a couple of poor media interviews," said one source.

Mr Clarke risked derailing his own policy when he told Victoria Derbyshire on BBC Radio 5 Live: "Assuming you and I are talking about rape in the ordinary conversational sense – some man has forcefully with violence..." Ms Derbyshire intervened, saying: "Rape is rape." Mr Clarke responded: "No it's not. And if an 17-year-old has sex with a 15-year-old and she's perfectly willing, that is rape." He added: "No one is saying a serious, proper rape case is going to be let out of prison after 12 months."

During a phone-in, a rape victim, identified as Gabrielle, warned Mr Clarke of the dangers to other women of allowing the earlier release of sex offenders, saying 90 per cent reoffended.

Mr Clarke's ill-fated remarks were spotted by Mr Miliband's aides. Half an hour before PMQs began, the Labour leader ripped up his pre-planned questions on health reforms and decided to "think on his feet" in the chamber, where he devoted all of his six questions to the Clarke controversy.

Mr Miliband said Mr Clarke's comments had implied there were "serious rapes and other categories of rape". He added: "The Justice Secretary can't speak for the women of this country."

The Prime Minister told MPs rape was "one of the most serious crimes that there is and it should be met with proper punishment". The "real disgrace", he argued, was that only 6 per cent of reported rape cases ended in a conviction. When Mr Cameron admitted he had not heard Mr Clarke's interview, Mr Miliband urged him to listen to it, adding: "The Justice Secretary should not be in his post at the end of today."

Last night Mr Clarke wrote to Gabrielle to say sorry for his remarks but stopped short of a full apology. "I haven't apologised," he told the BBC. "I apologise if an impression has been given that is not my view... My view is all rape is serious."

In an interview with Sky News, he said he would study the transcript of his comments, adding: "I'll make sure I give my views more clearly in future."

Women's rights groups expressed outrage. Vivienne Hayes, chief executive of the Women's Resource Centre, said Mr Clarke's comments "smack not only of ignorance but of outright misogyny". Anna Bird, the acting chief executive of the Fawcett Society, said: "Every year thousand of women across the UK are the victim of rape. To suggest that some of those rapes are not 'serious' is offensive and legally incorrect."

Ken Clarke on rape

* "I don't think many judges give five years for a forcible rape. The tariff is longer than that. And a serious rape, with violence and an unwilling woman... the tariff is much longer than that."

* "Date rape can be as serious as the worst rapes but, in my experience of being in trials, vary extraordinarily one from another, and the judge has to decide on the circumstances."

* "The classic rape when a man leaps out on an unsuspecting woman and forces her to have sex – that's 10 years-plus usually."

Changes to rape law

Amid deep concern about low conviction rates for rape, the laws defining the offence were updated in the Sexual Offences Act of 2003.

The Crown Prosecution Service regards all rape as serious, but views some as more grave than others. That is reflected in a sliding scale of punishments depending on the attack's circumstances.

Rapists can be jailed for life, but more typically repeated rape – of the same victim or of multiple victims – will receive a sentence of between 13 and 19 years, with judges instructed to take 15 years as their starting point.

Gang rape, rape involving abduction or kidnapping or a "sustained attack" will attract between six and 11 years in jail.

For a single rape by a lone offender, judges are directed to start at five years when passing sentence, although they can increase the term by three years or cut it by one year.

By Nigel Morris, Deputy Political Editor

Ken Clarke's day

10.20: Radio 5

Interviewed on BBC Radio Five Live to defend proposed reforms to rape sentences, Clarke appears to distinguish between "serious rape" and other rape. Presenter Victoria Derbyshire asserts: "rape is rape." Clarke says: "No it's not."

11.36: Sky News

In an attempt to defend his earlier statement Clarke claims that "rape has been singled out [by the media] mainly to add a bit of sexual excitement to their headlines but also because it is a very serious offence... Nobody gets back on the streets after a year and a bit." He also refers to "the classic rape when a man leaps out on a woman and forces her to have sex".

11.49: BBC News

Mr Clarke accused the media of "putting the most extraordinary spin on [the reforms]."

12.00: House of Commons

In Prime Minister's Questions David Cameron, left, responds to Ed Miliband's call for Clarke to be fired by saying: "I have not heard the interview but the position of the government is... that there is an offence called rape and anyone who commits it should be prosecuted, convicted and punished."

12.30: BBC studios

Due to appear on the Politics Show, Clarke leaves the studio, mug in hand, after seeing Prime Minister's Questions.

15.00: Sky News

Claiming to be "astonished" by the furore, Clarke says: "If I've given the impression that I do not regard all rape as a serious crime, I'll sit down and... see how on earth I gave that impression. I'll make sure I give my views more clearly in future."

15.50: BBC News

In an interview with Nick Robinson Clarke admits that he used the phrase "date-rape" inaccurately to describe underage sex but denies that his comments were offensive and says that "as far as I am aware I didn't say anything that Ed Miliband would disagree with." He added that: "People are slightly spinning and loading what I said in a way in order to get a false indignation. Rape is a serious crime."