Those people applying for visas to travel to the UK from countries with a record of immigration offending may have to pass biometric tests before being allowed in, the Home Office announced yesterday.

A pilot scheme in which fingerprints, iris or facial recognition data is contained in a microchip on visas for visitors from Sri Lanka is to be extended to countries from which there are large numbers of immigration offenders.

Visiting the Croydon processing centre with Tony Blair, home secretary David Blunkett said: "Biometrics can play a big part in tackling illegal immigration and abuse of our asylum system and by embracing it we can reduce the pull factor to the UK."

Meanwhile the government has also been accused of attempting to introduce a pilot test of ID card technology by the back door.

The six-month trial of biometric identification, which comes ahead of the introduction of a new high-tech passport in 2005, has been attacked by human rights groups.

The announcement comes as ministers prepare to reveal that they have met the prime minister's target of halving the number of asylum applications.