By Martin HickmanThe editor of the News of the World did not "volunteer" any information to the Metropolitan Police investigation into phone hacking, he told the Old Bailey today.Andy Coulson said that he did not want to "make the situation worse" following the arrest of the NoW's royal editor Clive Goodman, but he adamantly denied that he had tried to cover-up the scale of phone hacking at the tabloid.Giving evidence for the fifth day at the phone hacking trial, Mr Coulson said that he first heard of Mr Goodman's arrest in 2006 in a phone call to his home.He was at first unaware why Mr Goodman had been arrested, he told the phone hacking trial.Mr Coulson, then editor of the NoW, said: "I was told that Clive had been arrested and that the police were inside the office - or rather outside the office - waiting to come into the office."The police came onto the floor of the News of the World, and at some stage I was told where Clive was - and as the day wore on more information was being communicated."Asked when he learnt the nature of the police inquiry, Mr Coulson - who said he was only aware of an isolated episode of hacking involving the Home Secretary - replied: "It became apparent quite quickly that he [Mr Goodman] had been arrested for voicemail interception."He told the court he later learned that the police had arrested another individual, Glenn Mulcaire.Mr Coulson, whose newspaper was paying the private detective more than £100,000 a year - said: "I don't believe I had heard the name Glenn Mulcaire until after he had been arrested."He said he briefly phoned News International's ultimate owner, Rupert Murdoch, about the police investigation, saying it was the only time they discussed the subject.Mr Coulson said he could not recall the conversation but added: "There was something that Rupert Murdoch said during that conversation that stuck in my mind... 'the most valuable thing a newspaper had was the trust of its readers'."Mr Goodman told the court during his evidence that following his arrest Mr Coulson suggested he tell the police that he was a "lone wolf" and that no-one else at the paper had been hacking.Mr Coulson rejected that today, telling the Old Bailey that he went to meet Mr Goodman to discuss the case because he was concerned about his "well-being.""I was concerned for Clive," Mr Coulson said. "As his editor, I felt rightly or wrongly, that we had some duty of care for him."Asked if he had suggested a "lone wolf" defence, Mr Coulson said: "No, the lone wolf is not a phrase I would use."He also denied Mr Goodman's suggestion that he could influence the course of the case and had been in touch with the police and the Home Office. "What influence did I have to stop someone going to prison?" Mr Coulson asked. "I was feeling many things, but I wasn't feeling influential."Asked about the police inquiry - which resulted in the jailing of Mr Goodman and Mulcaire - Mr Coulson said: "I did not set out to volunteer information."I didn't want to make the situation worse than it was. But I didn't cover up anything. I didn't set up barriers."He was asked why on the day Mr Goodman pleaded guilty to hacking - 29 November 2006 - he emailed the Sun editor and his former lover, Rebekah Brooks, "it's all going so well today."Mr Coulson told the court: "I certainly didn't think it was going well. It was a disastrous day for the News of the World, for Clive Goodman and, as it turned out, for me."When I first read this I thought I was being sarcastic but I don't think that was the case. I think I was talking about the media coverage" - which he said he was pleased with because it was straightforward and not too big.He and Mrs Brooks deny conspiring to hack phones. Mr Coulson and Mr Goodman deny conspiring to commit misconduct in a public office. The trial continues.