The relationship between the police and the News of the World has come under fire again amid revelations that Neil Wallis, the former deputy editor of the News of the World, was paid by the paper's publisher for "crime exclusives" while working for the Metropolitan police.

Wallis was secretly paid more than £25,000 by News International after he left the paper and got a contract to work two days a month as a PR consultant with the Met. One story earned him a single payment of £10,000.

The Daily Telegraph claims that internal records obtained by Scotland Yard show that he was paid for providing News International with details of a suspected assassination attempt on the Pope during his visit to the UK last year.

A spokesman for Scotland Yard said the contract it had with Wallis's PR firm, Chamy Media, "had a confidentiality clause, a data protection act clause and a conflict of interest clause within it".

He added that Wallis did not have access to the Met's IT systems.

The revelations that Wallis received money from News International while working for Scotland Yard will raise questions about conflicts of interest.

Last month, it emerged that Andy Coulson, the former editor of the News of the World, continued to receive payments from News International as part of a severance deal after he was employed by the Tory party as its director of communications.

Wallis's solicitor has made a complaint alleging that the police had leaked the information regarding the payments.