Taxpayers could soon be paying more than £27,000 a year to keep mobile phone muggers in jail, even though the mobile phone companies have the technology to disable stolen handsets.

Mobile muggers could face jail sentences of up to five years under guidelines laid down yesterday by the UK's most senior judge, Lord Woolf the Lord Chief Justice.

Lord Woolf was speaking at an appeal court hearing over a plea by the Attorney General that a six-month detention sentence on a Manchester teenager who had stolen a mobile phone at knifepoint with two accomplices was "unduly lenient".

Thieves should expect a minimum 18-month jail sentence, rising to five years or more if it involves violence, Lord Woolf warned at the hearing.

"This will apply irrespective of the age of the offender and irrespective of whether the offender has previous convictions," he said.

The warning has again sparked controversy over the role of mobile operators in using cheap and simple technology that can render a stolen phone useless to the thief.

The Home Office rebuffed claims that it would be a more effective use of taxpayers' money to force mobile operators to make the phones less mugger-friendly than pay for keeping offenders in prison for five years.

It costs £27,566 to house each prisoner for a year, according to the government's figures for 2001.

A spokeswoman for the Home Office, said: "In order to tackle this we see a two-pronged approach and we need to make sure the sentences are appropriate to the crime and act as a significant deterrent.

"We welcome the Lord Chief Justice's call to the mobile industry to improve security and make the phones safer, and we are talking to operators about how to do this through a steering group."

She explained that the government will not consider legislation forcing operators to include the technology until these efforts have been exhausted.

The latest statistics from the British Crime Survey show that there were 470,000 mobile thefts from adults last year and 550,000 thefts from teenagers.