Violent crime on Britain's railways is on the increase, British Transport Police has said.

In its annual report, published on Tuesday, the force said that there had been a 2.3 per cent rise in reported crime in the year to the end of March this year.

And there was a 14 per cent increase in violent crime, it was revealed.

The figures prompted the Conservatives to warn that "crime is out of control and under Labour".

Violent crime on London Underground rose by 22.1 per cent, said the BTP, partly accounted for by a 29 per cent increase in assaults on Tube staff.

However, pick pocketing on the Underground, which accounts for 42 per cent of all of the network's crime, was down by 17.6 per cent.

"We have achieved all our objectives in relation to anti-social behaviour this year, with particular success against graffiti vandals," said BTP chief constable Ian Johnston.

"Dealing with anti-social behaviour is a top government priority and we are helping to achieve that, making our rail system more pleasant for the travelling public."

He added that the force would now be "looking for the same success in reducing violence against passengers and staff".

But shadow transport secretary Tim Yeo said said the figures "must be taken very seriously indeed".

"There is a real danger that the revelation of increases in violent crime and sexual assault will discourage more and more people from using public transport, especially if they think they are more likely to become a victim of crime," he said.

"These latest statistics show how crime is out of control and under Labour has got worse."

Bob Crow, general secretary of the RMT rail union, said the figures showed the need for "adequate staff on every station all the time they are open".

He also called for a guard on every train, including on the Tube.

"For too long rail employers have cut staff simply to save money, and the price has been an increase in assaults and abuse against our members," Crow added.

"CCTV cameras can help, but there is no substitute for an adequate presence of uniformed staff, backed up by a zero-tolerance policy from rail employers and a properly resourced and responsive transport police force."