A former Commons speaker has called for an end to "exploitation" of the NHS by foreign visitors.

Baroness Boothroyd quizzed the government in the Lords on Wednesday over whether action was being taken against the rising number of foreign nationals claiming treatment in the UK.

The issue of tourists who unlawfully obtain free medical treatment while visiting Britain has become a new part of the health agenda.

The former Commons speaker and Labour MP called for "an end to the exploitation of our NHS".

"What action is being taken to recover the amount owing to the National Health Service by overseas visitors?" she asked.

For the government, Lord Warner admitted ministers did not know the full extent of the problem.

"We do not collect information on this at the centre. Devolution is the world we now live in," he told peers.

"We do know that in 2001/02 £1.2 million was written off for uncollected debt."