Justice Secretary Ken Clarke brushed off calls today to apologise for his comments on rape sentencing but promised to "choose my words more carefully in the future".
Mr Clarke is facing continued pressure after sparking uproar by suggesting some rapes are more serious than others.
Leaving for work this morning, he insisted he was simply explaining a "long-standing factual situation".
He said: "I've always said that all rape is serious and I've no intention of changing the sentencing guidelines on rape, which always attracts serious imprisonment, quite rightly.
"Different rapes get different lengths of sentences from judges and always have, and they now follow sentencing guidelines which explain the different degrees of sentences.
"If I caused genuine offence to anybody by explaining that long-standing factual situation, then I must have made a very poor choice of words, so I will try to choose my words more carefully in the future."
Under pressure from 10 Downing Street, Mr Clarke was forced to tour the television studios last night to explain his remarks.
He also said "sorry" to a sexual assault victim who broke down in tears as she challenged him during a radio phone-in about his plans to halve jail terms in return for early guilty pleas.
But the apology failed to draw a line under the affair, with Labour continuing to question how he could remain in charge of justice policy for the coalition.
He is due to face his critics tonight when he is scheduled to appear on the BBC's Question Time - to be broadcast from Wormwood Scrubs prison with inmates in the audience.
The row came as he sought to defend Government proposals to offer a 50% reduction in sentences in return for early guilty pleas for offences including rape.
Speaking to BBC Radio 5 Live yesterday, Mr Clarke appeared to draw a distinction between date rape and "serious rape, with violence and an unwilling woman".
Put to him that "rape is rape", he said: "No, it is not."
Asked why rape sentences were on average only five years, he said: "That includes date rape, 17-year-olds having intercourse with 15-year-olds.
"A serious rape, with violence and an unwilling woman, the tariff is much longer than that. I don't think many judges give five years for a forcible rape, frankly."
Mr Clarke was confronted on the radio by Gabrielle Browne, the victim of an attempted rape, who broke down in tears as she denounced the 50% discount proposal as "a disaster".
The mother-of-two, 45, said she had fought for 688 days to have her attacker brought to justice, only for him to have his sentence reduced for a guilty plea. She told Mr Clarke: "It happened to me. It's a disaster, especially with sex offenders."
In an excerpt of the letter he last night sent to Mrs Browne, the Justice Secretary said: "I have always believed that all rape is extremely serious, and must be treated as such.
"I am sorry if my comments gave you any other impression or upset you."
Speaking to The Sun after waiving her right to anonymity, Mrs Browne called for the under-fire Justice Secretary to resign, claiming he is "endangering women".
She said: "We cannot have British women fearing for their safety. Women are not safe in his hands. I honestly do not believe he can continue in his position."
Labour leader Ed Miliband seized on Mr Clarke's comments and called on David Cameron to sack the veteran Cabinet minister.
Downing Street said that Mr Clarke had the Prime Minister's confidence but refused to confirm whether Mr Cameron had personally ordered him to go back onto the airwaves to explain himself last night.
Asked about Mr Clarke's position today, Transport Secretary Philip Hammond said: "The Prime Minister has confidence in the Justice Secretary. Ken is doing a very difficult job in very difficult circumstances."
Speaking on BBC1's Breakfast programme, Mr Hammond said: "Perhaps he (Mr Clarke) didn't get his point across as he wanted to. The problem we are facing is that 94% of rapists go unpunished."
Mr Hammond said the Government would listen carefully to public reaction to the 50% sentence reduction proposal.
Leaving his home this morning, Mr Clarke said: "What I described was a long-standing factual situation which doesn't affect my reforms.
"I've made no proposals to change the sentencing for rape, I've made proposals on the discount made for a guilty plea. People are punished more if they make the witness go through the ordeal again, but that's a very long-standing arrangement which has always applied to all crimes."
He laughed off suggestions that he should resign, saying: "I've encountered ministers resigning for proposals they haven't made, but to resign for proposals I've never made or thought of making would be just a little odd, I think."
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