"I want to thank Ambassador Kirk for his hard work on behalf of the American people over the past four years," the president said in a statement from the White House. "There's no question Ron delivered results for the American people and for our economy. From bringing home new trade agreements with Korea, Colombia and Panama and negotiating to open up new markets for American businesses, to cracking down on unfair trade practices around the world, he has been a tremendous advocate for the American worker. As a former mayor [of Dallas], Ron was relentless in making the case to the American public that a balanced, thoughtful trade policy can contribute to a stronger economic future for America. I appreciate his service and wish him the best of luck."
Kirk, 58, a former two-term mayor of Dallas, assumed the post of U.S. trade representative in March of 2009, The Dallas Morning News said.
The trade representative is a Cabinet-level official, but not actually a member of the Cabinet.
Kirk's achievements included shepherding the implementation of long-term trade agreements between the United States and Korea, Colombia and Panama that originated during George W. Bush's administration, CNN reported.
The departure of Kirk, an African-American, comes amid criticism that Obama's second-term team lacks diversity.
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