LONDON — Britain’s defense minister, Liam Fox, resigned abruptly on Friday after more than a week of damaging newspaper headlines about his personal and professional relationship with a 33-year-old man who accompanied him on numerous official trips abroad and appeared to have brokered access for wealthy people who shared Mr. Fox’s interest in fostering still closer ties with the United States and Israel.  Liam Fox, until Friday a British cabinet official.  Follow @nytimesworld for international breaking news and headlines.  The resignation of Mr. Fox, one of the most senior figures in the British cabinet, was a major blow for Prime Minister David Cameron’s 17-month-old government and Mr. Cameron’s Conservative Party, which counts Mr. Fox as the effective standard-bearer in the cabinet for the party’s right wing. A desire to avoid alienating the powerful right-wing bloc of Conservative backbenchers appeared to have been one reason Mr. Cameron had not already ousted Mr. Fox.  Mr. Cameron quickly replaced him with Philip Hammond, the transportation secretary. Mr. Hammond, in turn, was replaced by Justine Greening, formerly a junior treasury minister, an appointment that should soften criticism that Mr. Cameron’s cabinet has few women in powerful posts.  Mr. Fox revealed his decision to quit in a letter to Mr. Cameron, effectively pre-empting an internal inquiry the prime minister had ordered into his relationship with his close friend, Adam Werritty. The official charged with the inquiry, Britain’s top civil servant, Gus O’Donnell, had been expected to submit his findings next week, and there was a widespread expectation that it would be harshly critical and force Mr. Fox out.  Mr. Fox’s resignation letter made no mention of Mr. Werritty, his companion on 18 trips abroad while Mr. Fox was defense minister. According to Defense Ministry records, Mr. Werritty was also at a number of meetings Mr. Fox held with senior foreign officials, including a dinner in Tampa, Fla., in July 2010 with American military officials, including Gen. John R. Allen, now the NATO commander in Afghanistan.  Official records made public in recent days showed that Mr. Werritty, born in Scotland, like Mr. Fox, and best man at his wedding in 2005, had also visited him 22 times in the Defense Ministry headquarters since the May 2010 elections that put the Cameron government in office. At one point in the Conservatives’ years in opposition, the two were London roommates, in a property whose mortgage was paid out of Mr. Fox’s parliamentary expenses.  “As you know, I have always placed a great deal of importance on accountability and responsibility,” Mr. Fox said in his resignation letter, which was released by his aides. “As I said in the House of Commons on Monday, I mistakenly allowed the distinction between my personal interest and my government activities to become blurred. The consequences of this have become clearer in recent days. I am very sorry for this.”  He added: “I have also repeatedly said that the national interest must always come before personal interest. I now have to hold myself to my own standard. I have therefore decided, and with great sadness, to resign from my post as secretary of state for defense — a position which I am immensely proud and honored to have held.”  Mr. Cameron responded with a letter that said he was “very sorry” to see Mr. Fox go and lauded his performance in the defense post, which included overseeing Britain’s participation in the conflicts in Afghanistan and Libya, as well as the harshest cuts in Britain’s defense budget in decades. Those were part of broad and painful spending reductions as the Cameron government grappled with a debt and deficit crisis.  “You have done a superb job in the 17 months since the election, and as shadow defense secretary before that,” Mr. Cameron said, calling Mr. Fox’s tenure a time of “fundamental changes in the Ministry of Defense and in our armed forces” as they modernized.  “On Libya, you played a key role in the campaign to stop people being massacred by the Qaddafi regime and instead win their freedom,” he said, adding, “I appreciate your commitment to the work of this government, particularly highlighting the need to tackle the deficit, and the relationship between Britain’s economic strength and our national security.”
Liam Fox resigned on Friday after days of searing headlines about revelations that he had given a close friend extensive access to his official activities.