The home secretary has unveiled measures to toughen Britain's firearm laws ahead of a multi-agency crackdown on "gun culture".

With New Year headlines dominated by the Birmingham gang shooting and a London armed siege over the Christmas period, David Blunkett has outlined legislation to impose a minimum five-year jail term for anyone caught carrying a gun.

Downing Street admitted on Monday that crime figures to be released by the Home Office on Thursday will show a marked increase in gun crime.

"There has been a significant rise in gun crime which we have to address," said the official spokesman.

Mandatory sentences will be added to the Criminal Justice Bill ahead of an emergency summit to tackle "gun culture" on Friday.

"We will not tolerate an escalation of the number of guns on our streets," the home secretary said.

"While we already have some of the toughest gun laws in the world, there has been an unacceptable increase in the flagrant use of guns in crime across the country."

"The government is determined to tackle this head on and is introducing new legislation that reflects the seriousness of the offence."

Blunkett's aim is that a new mandatory minimum sentence will cover those guns most heavily used in crime, such as handguns and automatic weapons.

The new sentence will apply to anybody convicted, on indictment, of possession or distribution of prohibited firearms or ammunition.

In 2001, 757 people were convicted for possession or distribution of prohibited weapons and 131 were sentenced to immediate custody with an average sentence of 18 months.

Ministers are concerned that though gun crime remains statistically rare incidents, such as the Birmingham double-killing, have a disproportionate impact on communities.

Figures out on Thursday are expected to show an increase on the 7362 recorded crimes in which firearms were reported to have been used in 2000/2001 - a figure that is 0.1 per cent of all recorded crime.

"Protecting the public and police officers must be our paramount concern. Although the number of incidents remains relatively small, the impact of armed crime on communities is devastating," said Blunkett.

"We're determined to support victims and their families by bringing to justice drug gangs and organised criminals who have no respect for human life."

"Introducing a tough minimum sentence for criminals caught with illegal firearms will send a clear message that serious, violent offending will invariably be dealt with in the strongest manner."

Senior police officers, including Metropolitan Police chief Sir John Stevens, have lobbied ministers to bring in tough new gun laws in a bid to beat a wave of crime driven by the hard drugs trade.

Stevens welcomed the move as part of a wider strategy to combat gun crime.

"I have made no secret of my support for mandatory prison sentences for firearms offences; it is essential that we make it clear to criminals that the use of guns will not be tolerated on our streets," he said.

"The support of the judicial system is needed in delivering meaningful sentences if a real impact on gun crime is to be made. The growing culture of the casual carrying of handguns, both real and imitation, must be brought under control as soon as possible."

The idea drew a cool response from prison reformers who argue that tackling social exclusion would achieve better results.

Former prison governor professor David Wilson said the tough regimes ordered by past and present home secretaries had made little impact.

"If sentencing had any part to play in reducing the crime rate, Britain would have the lowest crime rate in Europe," he told the BBC.

Lib Dem home affairs spokesman, Simon Hughes is also opposed to a mandatory five-year sentence for gun possession.

"Fixed penalties are always inflexible...to set fixed minimums means that you can't so easily distinguish between the person who is fifteen, maybe peripherally carrying something for someone else, the most inoffensive and least dangerous weapon, and the sub-machine gun which someone clearly took out with them and in Birmingham last week," he said.

Ministers are concerned that issues from firearm smuggling, replica guns and teenage culture are fuelling a crime wave.

Blunkett has highlighted evidence showing "that the problem of possession of handguns lies predominantly with young people who carry weapons for self-protection or as a means of gaining respect or revenge, often related to dealing in or the use of drugs".

And he has announced a summit with top police officers, customs, crown prosecutors, immigration officials and community representatives to look at firearm and drug crime, gang warfare, international and how best to harness community involvement in tackling gun culture.

Others have urged the music industry to take a more responsible stance following controversy over rap and garage music lyrics and videos that, some claim fuel gun culture.

Culture Kim Howells has been accused of racism after saying it is time to stand up to the "idiots" of rap culture.

"The events in Birmingham are symptomatic of something very, very serious. For years I have been very worried about these hateful lyrics that these boasting macho idiot rappers come out with," he said.

"It is a big cultural problem. Lyrics don't kill people but they don't half enhance the fare we get from videos and films. It has created a culture where killing is almost a fashion accessory."

The Liberal Democrats have urged broadcasters, record executives and politicians to adopt a code of conduct stopping the showing of music videos that glamorise guns and violence.

Hughes said the music media must shoulder its responsibilities.

"I think it's now very urgent. The likes of MTV and others who are rock and pop video channels have to come with the rest to some agreement as to what's at stake... I think guidelines could be drawn up, and it's about making sure what people see as glamorised doesn't pick up fourteen, fifteen and sixteen year olds who...might be encouraged [to join gangs]," he told the GMTV Sunday Programme.

The south London MP also called on the black community to pressure musicians not to glorify violence in music or videos.

"The black community in particular have to say to each other we are not going to let you get away as setting this as a role model for the next generation... the best people to do that are the women in the community," he said.

But Conor McNicholas, editor of the music magazine NME, described attacks on black music culture "deeply racist"."It is this idea again that we have to do something about these out-of-control black people in our streets and the nasty culture they are perpetuating," he said.