Nicholas Burns, the third ranking US diplomat who spearheaded the US push to enact UN sanctions on Iran and negotiate a nuclear cooperation agreement with India, announced Friday that he was resigning from his post, told dpa .
Burns has served as undersecretary for political affairs since March of 2005, overseeing US foreign policy in each region of the world.
Burns, 51, told reporters he was stepping down to spend more time with his family.
"After 26 years in government service it's time for me to meet my obligations to my wife and three daughters and it's time to pursue other ventures outside the government," Burns said.
He will stay in his position until March and will attend next week's meeting in Berlin of the five permanent members of the UN Security Council - Britain, China, France, Russia and the United States - plus Germany about Iran, Secretary of State Condoleezza Rice said.
Burns served as the permanent US representative to NATO prior to his current job, and had previously served as ambassador to Greece, State Department spokesman and on the National Security Council.
"He is deeply respected and admired here in Washington, but also deeply respected and admired abroad, where he has been the consummate diplomat serving on behalf of the United States in some of our most difficult circumstances," Rice said.
Burns led US negotiations with the other four members of the Security Council to enact two rounds of sanctions on Iran because of the Islamic state's refusal to suspend uranium enrichment.
He also completed complex and difficult negotiations with India to hammer out an agreement allowing the United States to share civilian nuclear energy technology with India.
US President George W Bush and Indian Prime Minister Manmohan Singh inked the deal in March 2006, but its implementation has been held up because of differences in India's coalition government.
Rice said that even once Burns is in retirement from the Foreign Service, she has asked him to continue working on the nuclear agreement with India - a request Burns accepted.