An NHS trust's seven-and-a-half-year legal fight to uncover the mole who leaked details of Moors Murderer Ian Brady's treatment while on hunger strike is to continue, despite estimated costs of over £1m.

Last month the Appeal Court refused Mersey Care trust the right to take freelance journalist Robin Ackroyd to the House of Lords in an attempt to get him to reveal the source of his 1999 Mirror story about Brady's treatment at Ashworth Special Hospital (now part of Mersey Care).

Ashworth took the Mirror, and subsequently Mr Ackroyd, to court and the House of Lords ordered the newspaper to disclose its source. Now after years of lengthy wrangling the Appeal Court has refused Mersey Care any further appeal, saying disclosure would not be in the public interest.

But in a statement, Mersey Care said: 'We are exercising our right to go directly to the House of Lords to request permission to appeal.'

The trust says the appeal judgement means that confidential medical records do not have the high level of protection which the House of Lords had intended when it gave its judgement in the Mirror case - which Mersey Care trust believes is identical in all particulars to the current case concerning Robin. Ackroyd.'

The case has already cost the trust over£320,000. The National Union of Journalists, which backed Mr Ackroyd, says Mersey Care is wasting taxpayers' money as it will be forced to pay his legal costs of£500,000 and that the total bill will break the£1m barrier.