The Sun has a 7ft-high safe stuffed full of unpublished photographs, stories and videos of people in public life, one of its former executives told the paper's corruption trial.

Ben O'Driscoll, who denies three counts of conspiring to commit misconduct in a public office, described the safe as he began his defence.

The former deputy news editor said that the Sun carefully assessed stories involving "confidential" information and the editor would decide whether publication was in the public interest.

He told Kingston Crown Court that those stories that were not in the public interest ended up in the safe in the middle of the newsroom.

Mr O'Driscoll, who left the Sun in 2011 to become deputy news editor of the Daily Mail, where he still works, told the trial: "There was an enormous safe, 7ft high – it looks like something out of the Wild West – and that safe is full of about 30 years of stories which are confidential and did not pass the public interest test."

What's in there is quite eye-popping, I must say."

He went on: "It would be photographs, videos, reports; ordinarily it would involve MPs, celebrities... there are royals in there. If you were to publish everything in that safe The Sun's circulation would go up."

Mr O'Driscoll said that he was innocent of the charges against him.

He denied a claim made by a former colleague, district reporter Jamie Pyatt, that he had been informed about Mr Pyatt's meetings with public officials.

Mr O'Driscoll, who had been sitting close to Mr Pyatt in the glass-fronted dock moments before, said: "It pains me greatly to say this but Mr Pyatt was not telling the truth."

Asked by Judge Richard Marks for further clarity, Mr O'Driscoll said: "I think Mr Pyatt said yesterday that he told the newsdesk when he was meeting public officials and was updating us about those meetings. He said he kept us updated of any story he was working on that involved a public official."

Mr O'Driscoll's lawyer, Martin Hicks, asked: "So would you receive any calls of that nature from him?"

The former executive replied: "Never.""Or from any other journalist?"

Mr O'Driscoll replied: "Never.""Or any emails about who he was going to meet or the product of that meeting?"

Again, the journalist replied: "Never."

Mr Pyatt, Mr O'Driscoll and four other Sun journalists deny conspiring to commit misconduct in a public office. The case continues.