Changes to the law and improvements in support services had failed to stem attacks, she told the Guardian, adding that some offenders felt victimised when their actions were questioned.

"We need to focus on men's behaviour and teach men they have some responsibility ... Men don't bother to find out [where the boundaries are] in some cases," Ms Mactaggart said. "We have done a lot of things to help victims of rape ... and it still keeps happening.

"It seemed to me that we need some really active crime prevention here, and one of the strange things about this offence is the way in which victims commonly feel responsible, and perpetrators sometimes feel victimised. What we are doing so far isn't working."

Ms Mactaggart said she hoped that challenging men's attitudes would also give women confidence that the law was on their side to help tackle ongoing problems of underreporting. "Women do recognise it as a crime. The problem is they think it's their fault," she said.

The minister was speaking ahead of a ?500,000 advertising campaign urging men to ensure that their partners consent to sex which will be launched in men's magazines such as Nuts and Zoo as well as on the radio and on posters in the men's toilets of bars and clubs this week.

Using provocative imagery and down-to-earth language, it will warn that consent is active, not passive, and that unless women actively say yes, men must assume the answer is no. "I'm going to have a bad time ... [but] you have got to be prepared to use language and media that are not normal suspects for government advertising," said Ms Mactaggart. She said the government needed to make people aware of the consequences of their actions "quite starkly".

"We've been through campaigns encouraging women to make themselves more safe. Let's try saying to the perpetrators: you think of yourself as just a lad having fun, but have you ensured that this woman wants this and has said yes? Because if you haven't, there might be consequences."

The 2003 Sexual Offences Act says a person must have the "choice, freedom and capacity" to assent to intercourse. But the solicitor general, Mike O'Brien, said last week that the law might need clarification on the question of whether a woman who was drunk could give consent, in the light of several cases which have been thrown out of court.

The government will publish proposals to improve the conviction rate for rape, such as allowing expert witnesses to explain victims' behaviour to juries. Home Office research last year showed only 655 out of 11,766 rape allegations (5.6%) had ended in a conviction.

The Home Office believes attitudes towards rape are also a problem. A recent Amnesty International survey found that more than a quarter of people in the UK believed a woman was at least partly responsible for being raped if she was drunk.

Rape charities expressed concern this weekend about a reported 15% reduction in sentences for sexual offences to be outlined in guidelines from the independent sentencing advisory council.

But judges are already using the discount for all sentences longer than 12 months - whatever the crime - after the introduction of longer supervision periods after prisoners' release on licence. In addition, the most dangerous rapists are now receiving a new indefinite sentence, imprisonment for public protection.