Court hears of six-year affair between Brooks and Coulson Rebekah Brooks had an affair with Andy Coulson "for at least six years" dating back to 1998, the jury in the phone hacking trial has been told. The police found a letter dated February 2004 in a computer at her London home relating to the relationship, the court heard. In a case that goes to the heart of the British establishment, the trial places Mrs Brooks, who became one of Rupert Murdoch's most trusted executives and a friend of David Cameron, the prime minister, side-by-side in the dock with Mr Coulson, who became one of Mr Cameron's most senior aides. Both were part of an alleged conspiracy, along with two other defendants, at the defunct tabloid that hacked into the voicemails of a dozen high-profile figures, it has been claimed. Part of the letter that Mrs Brooks had written to Mr Coulson as he was trying to break off their "secret" affair was read out to the jury by Andrew Edis QC, who said it had caused her "a great deal of grief." In it Mrs Brooks described Mr Coulson as "my very best friend" and "I tell you everything . . . I seek out your advice . . . I love you," she added: "Without our relationship in my life I'm not sure I'll cope." She added that his absence "fills me with dread." Mrs Brooks was deputy editor of the Sun in 1998 until 2000 when she was made editor of the News of the World. In 2003 she moved back to edit the Sun. Mr Coulson was associate editor of the Sun from January 1998 until August 1999. He became deputy editor of the News of the World in 2000 and edited the title from January 2003 until January 2007. The affair covered the crucial period in 2002 when the News of the World hacked the phone of murdered teenager Milly Dowler, the court heard. Mr Edis told the jury that when parties were party to a conspiracy a key question was how well they knew each other. He told the jury that Mrs Brooks was aware of phone hacking. He referred to a lunch she had had with Eimear Cook, former wife of golfer Colin Montgomerie in 2005. Mrs Brooks is alleged to have told Ms Cook all you needed was someone's mobile and factory pin numbers and you could listen to their voicemail, the court heard. She is alleged to have told Ms Cook that the story involving Sir Paul McCartney and wife Heather Mills about her engagement ring had "come from phone hacking." The court had earlier been told that Mrs Brooks oversaw a crackdown on spending when she was editor of the News of the World between 2000 and 2003 and so must have known about the "special arrangement" to pay convicted phone hacker Glenn Mulcaire. Mr Edis painted a picture for the jury of a "dog-eat-dog world" of tabloid journalism in which journalists sometimes "strayed into criminality" in pursuit of exclusive stories. He detailed emails showing that Mrs Brooks took steps to bring editorial spending under control - for instance admonishing a journalist for spending £7,500 for a minor story - but now claiming ignorance of a £92,000 contract to Mr Mulcaire. In emails to her staff that were read to the jury, Mrs Brooks threatened "the most severe consequences if anyone goes over budget" and suggested to managing editor and co-defendant Stuart Kuttner that he authorise any payment over £2,000. Mr Kuttner said in an email that he would be "unavoidably tough on budgets and the palmy days of indulgence are over." Mr Edis told the court that in a culture of tough budget control at Rupert Murdoch's tabloid empire, "a major exception was created for Mr Mulcaire and that couldn't have happened without them knowing about it." There was close financial management going on but all the while there were substantial sums of money being paid out to Mr Mulcaire with no one questioning it at all. Mr Mulcaire, who had worked for the News of the World since 2001, had a contract to work exclusively for the newspaper but appeared in few corporate records as "his existence had to be concealed," Mr Edis claimed. "The special arrangements for Mr Mulcaire were very significant," he said. The three senior management defendants . . . must have known what it was for, otherwise they would never have allowed it. When Mr Coulson took over as editor of the News of the World in 2003, Mr Mulcaire's annual pay was increased to more than £100,000. The jury was told on Wednesday that three former journalists at the News of the World had now pleaded guilty to conspiracy to intercept voicemails, suggesting that criminal activity went well beyond one rogue reporter who had been convicted in 2007. Mr Mulcaire pleaded guilty earlier this year to hacking the phone of murdered schoolgirl Milly Dowler and other counts of conspiracy to hack phones. The eight defendants are charged with a number of offences, all of which they deny. The case continues.