Stalkers and wife-batterers could be electronically tagged to prevent them approaching their victims, it has emerged.

Under the plan, the authorities would be alerted when violent partners or obsessives entered an area from which they had been banned by the courts.

Prime Minister Tony Blair revealed the idea was being studied by ministers in an interview on BBC1's Breakfast With Frost programme. "We are now considering electronic tagging for domestic violence and stalking cases," he said.

His comment follows praise for the introduction of tagging more than three years ago.

Downing Street said later that the tags, which are seen as an alternative to jail, have a 95% compliance rate.

In stalking and domestic violence cases, they would be used to monitor the effectiveness of injunctions and other restrictions imposed by the courts, No 10 said.

Backing for 'stop and search'

In the same interview Mr Blair also urged police to use their stop and search powers following Home Office figures last month pointing to a decline in their use in two force areas.

Metropolitan Police officers have been reportedly reluctant to stop ethnic minority suspects after the Stephen Lawrence inquiry report which criticised the force's "institutional racism".

In December, Home Office figures showed a decline in stop and search for all ethnic groups in the Metropolitan Police and in the West Midlands Police.

The figures showed an increase in stop and searches in many other police force areas.

Mr Blair said: "I think it is important to emphasise, particularly to the Metropolitan police - which has had a difficult time after the Lawrence Inquiry - that the stop and search powers are there and should be used.

"We have got to back the police when they do use them. I think they are a very important part of the weapons the police have in order to fight crime, particularly street crime."

Mr Blair's comments come ahead of his meeting with the new Metropolitan Police Commissioner, John Stevens, on Tuesday.

The meeting will coincide with the publication of new crime statistics.