The inner circle of advisers who have for so long surrounded and protected President Bush became tighter still yesterday with the announcement that Dan Bartlett was leaving the White House to pursue a new job outside government.

Although still only 36, he is the President’s longest-serving aide, having started work for him nearly 14 years ago when Mr Bush first ran for Governor of Texas.

Mr Bartlett’s title is “Counsellor to the President”, an adviser at the heart of decision-making. But he also regularly appears in the media as a trouble-shooter, defending Mr Bush on everything from the war in Iraq to Hurricane Katrina and the Republicans’ defeat in last year’s Congressional elections.

He is known to have Mr Bush’s ear, one of the few people who can give the President bad news or tease him about wearing a brown suit so disliked by aides that it has been nicknamed “Big Brown”.

Joshua Bolten, the White House Chief of Staff, said yesterday: “He can talk to the President in a candid way, in a sort of a family way, that almost nobody else can. He can talk to him about Big Brown, he can joke with him. He’s got the Texas roots that make it possible for them to talk about characters in Texas politics or Longhorn football or Texas Rangers baseball. He’s been a good friend of the President as well as a counsellor.”

His departure symbolises the shrinking influence of the “Texas mafia” who followed Mr Bush from the state governorship to the White House. Karen Hughes left after the 2004 election to take on a new outreach role at the State Department, Scott McClennan was removed as White House press secretary last year, while Harriet Miers quit as Mr Bush’s legal adviser earlier this year.

Those who remain such as Karl Rove, the President’s chief adviser and strategist, and Alberto Gonzales, the Attorney-General, have been tainted to varying degrees by scandal and controversy in recent months.

Mr Bartlett, who worked with Mr Rove’s Texas-based consulting company before teaming up with Mr Bush, said yesterday that with 3-year-old twin boys and another son born in January, it was time to “reacquaint myself with my family”.

He once again defended the President and the war in Iraq, saying: “It will be one of those things, when I hang up the spurs for the last time, I’ll be able to look in the mirror and say, ‘I know this President and this White House did what they thought was right’. And at the end of the day, that’s all you can do.”

Times Recommends

• Please help: maimed children of war want their lives back
• Cabal seizes diamond riches to buy power
• White House gatecrashers got to the president