Details of public contracts kept from taxpayers' view: Taxpayers are denied information on terms of deals. Tim Kelsey reports

More than half of all government contracts are not legally declared and details of their cost and conditions are withheld from taxpayers' scrutiny.

Privatised utilities are also acting in breach of European law by failing to declare details of contract awards, according to a survey by the Independent and Euro-Bid Watch, an information services consultancy advising companies on European and international contracts. The worst government offender is the CCTA, the much-criticised agency responsible for computer contracts. It gave details of awards in under one-tenth of its contracts.

Among privatised utilities, Norweb acted most in breach of European law, by failing to declare any contract awards in the past 12 months.

The results of the survey will provoke renewed concern about the extent to which Britain is ignoring strict European rules about disclosure of information to its taxpayers.

Luxembourg, by contrast, published full details of contract awards in 85 per cent of cases. Countries are allowed to withhold information only when it is against the national interest to do so. Britain is not the worst offender.

Nationally, Spain declares only 2 per cent of its contract awards.

Britain is required under European law to publish invitations to tender for contracts, and also to publish details of who won the contract and its approximate cost. This is required because it affords taxpayers' insight into the costs of contracts, and also because it supports fair trading.

The survey compared the number of contracts put out to tender against the number of those for which there are published details of an award.

The Scottish Office proved the most efficient by publicising just over half of its awards. The Inland Revenue gave details of 43 per cent; the National Rivers Authority 20 per cent; and the City of Westminster only 16 per cent.

The CCTA, which recorded the lowest number of publicised awards, yesterday denied flouting European rules but claimed some of the contracts for which it put out the tender were later awarded by another government department.

Among the privatised utilities, Nuclear Electric declared 51 per cent of its contracts; National Power half; and the Civil Aviation Authority only 11 per cent. The worst performer was Norweb which published no information on contract awards.