Christopher Hill, a career foreign diplomat who has served mainly in Europe and Asia, turned his sights to Iraq when he became U.S. ambassador to the country in April 30, 2009.

At his previous post as assistant secretary of state for East Asian and Pacific Affairs, Hill was lead negotiator in six-nation talks aimed at dismantling North Korea's nuclear program. He also was the top negotiator for the Dayton Agreement ending the war in Bosnia.

"Ambassador Hill has been tested, and he has shown the pragmatism and skill that we need right now," President Obama said when naming him to the post on Feb. 27, according to news services.

While Hill was lead negotiator on the North Korea nuclear issue, the North made a landmark agreement with the other parties -- the United States, South Korea, Japan, China and Russia -- to end its nuclear programs in exchange for energy assistance.

In an October 2007 interview on the NewsHour, Hill said that after the North abandoned its nuclear program, the United States would seek to normalize relations.

"We'd look to work on a peace arrangement on the Korean peninsula and to end what has essentially been a state of war and replace it by a peace process," he said. "So there's a lot on the table there for the North Koreans, if they're really interested in going the full distance and getting rid of these nuclear programs."

But the negotiations hit an impasse in late 2008 over a dispute as to how North Korea would verify its nuclear disarmament.

In January 2009, Hill acknowledged that North Korean disarmament talks had been "a pretty tough assignment" and that there had been "too many interruptions" in the negotiations, Agence France-Presse reported.

Before his work on North Korea, Hill served as ambassador to Poland from 2000 to 2004, ambassador to Macedonia from 1996 to 1999 and special envoy to Kosovo from 1998 to 1999, according to the State Department's Web site. He also served as special assistant to the president and senior director for Southeast European Affairs in the National Security Council.

Hill was former U.N. ambassador Richard Holbrooke's deputy at the Dayton peace talks in 1995. Holbrooke described Hill as "brilliant, fearless and argumentative" in his book on the Dayton negotiations, according to the Washington Post.

Hill graduated from Bowdoin College in Brunswick, Maine with a bachelor's degree in economics and earned a master's degree from the Naval War College in 1994.

-- Compiled from wire reports and other media sources