Phillips, the former husband of the Princess Royal and the father of world eventing champion Zara, has overseen the most successful period in the history of US eventing, leading them to 23 team and individual medals since taking over in 1992 and has never returned home from a major event without at least one medal, including four consecutive Olympics.

His successes have included team silver and individual bronze at the 1996 Olympics in Atlanta, team bronze and individual gold at the 2000 Olympics in Sydney, team bronze and individual silver at the 2004 Olympics in Athens and individual silver at the 2008 Olympics, when the equestrian events were held in Hong Kong.
His teams also won team gold at the Pan American Games in 1999, 2003 and 2007 and team gold at the 2002 World Equestrian Games.

As a rider, Phillips had just as a successful career, winning a team Olympic gold medal at Munich in 1972 and gold medals at World and European championships, as well as four times at Badminton and once at Burghley.
He also won a team silver at the 1988 Seoul Olympics, riding for Britain.

Phillips married the Princess Royal [or Princess Anne as she was then called] at Westminster Abbey in 1973 but the couple divorced in 1992.

He married dressage rider Sandy Pflueger, who represented the US in the 1984 Olympics in Los Angeles, in 1997.

The United States Equestrian Federation (USEF) have already begun the search for Phillips' successor and plan to advertise the role later this year.

Phillips will be just a few days short of his 64th birthday at the end of the London Olympics.

He said: "It's time to give someone else the opportunity to put their stamp on the programme."

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