Trusts have earmarked £150m for replacing medical equipment that will fail because of the year 2000 computer bug, according to the National Audit Office.

The figure comes on top of the estimated£170m-plus cost of rooting out the bug from NHS information systems.

The£330m total does not include the cost of fixing or replacing GP systems, which could be anywhere between£60m and£120m, says the report.

The bug will consume almost the whole of the NHS's annual computer systems budget, plus 18 months' medical equipment budget. More than half is to be spent this financial year.

But the Department of Health is still insisting that costs must be met from existing budgets, while the NAO claims the bug-proofing operation is costing much less than in similar sized private sector organisations.

NHS Confederation chief executive Stephen Thornton demanded 'new money and technical assistance, not civil servants monitoring our performance'.

More than 20 per cent of trusts did not think they could bug-proof all their information systems and medical instruments before December 1999.

The DoH has now ordered all NHS bodies to submit quarterly progress reports. It has also set an extra 'last ditch' NHS-wide checkpoint for 30 September 1999.

Managing the Millennium Threat II. National Audit Office. 0171 798 7400.£9.85.