People coming to live and work in Britain should be subjected to tests for diseases such as TB and HIV, the Conservatives have said.

The party says its policy is modelled on systems already in use in Canada and New Zealand.

Determined to prove it is equally tough on immigration, Labour insisted it was already seeking to screen high risk entry clearance applicants for TB.

Under the Tory plans people coming to Britain on a temporary basis for less than six months will not be required to undergo a medical test unless they intend to work in health care, childcare or teaching.

But anyone coming to Britain from outside the EU on a temporary basis for over six months but less than 12 months from a high incidence TB country will be required to undergo a chest X-ray followed up by tests if necessary.

People coming to settle in Britain permanently from outside the EU will have to demonstrate that they have an acceptable standard of health.

"It's very important that we should safeguard the good standards of public health that Britain enjoys," Howard said on Tuesday.

"I don't think a responsible government can stand aside and do nothing in the face of this problem."

TB issue

Only TB will automatically preclude the grant of a visa. All other conditions will be dealt with on a case by case basis and will be assessed on what costs, if any, they will impose on the NHS.

The proposals will not affect asylum applicants' claims.

"Conservatives do not believe that people genuinely fleeing persecution should be denied refuge because of their health," said the party.

Michael Howard said the British people "deserve the best standards of public health".

"We need to control who is coming to Britain to ensure that they are not a public health risk and to protect access to the NHS. It's plain common sense," added the party leader.

"And it's exactly what they do in New Zealand, Canada and Australia. At the next election people will face a clear choice: limited and controlled immigration under the Conservatives or unlimited immigration under Mr Blair."

Catch-up

The Conservative policy pledge prompted an immediate rebuttal from Labour.

Immigration minister Des Browne said the government was already committed to targeted screening for TB.

"Our approach to health checks is based on expert medical advice on protecting the nation's health. We follow the expert advice and keep it constantly under review," he said.

"The Tory policy is little more than a desperate attempt to catch up with Labour's five year plan.

"It is uncosted, untested and would take Britain back to the chaos that reigned in immigration when Michael Howard was home secretary."

The plan was dismissed as "irresponsible" by Liberal Democrat leader Charles Kennedy.