The U.S. Embassy in Kabul confirmed Tuesday that Ambassador Ryan Crocker will resign this summer for health reasons. The development follows high-level multilateral talks over bringing the Afghanistan War to an end at the NATO summit in Chicago over the weekend.

Ambassador Crocker confirmed that he intends to depart Afghanistan for health reasons in mid-summer, following the Kabul and Tokyo conferences, said embassy spokesman John V. Rhatigan via email Tuesday. Beyond that, we have nothing further on this topic at this time.

Crocker, one of the U.S.'s top diplomats and Middle East experts, was appointed to the Kabul embassy 10 months ago and previously served as ambassador to Iraq, Kuwait, Lebanon, Pakistan and Syria over a period of two decades.

The ambassador was present at the just-concluded NATO summit, where the U.S. and its coalition allies agreed to transfer combat roles from NATO troops to Afghan security forces next summer with the intention of bringing NATO's role in the war to a close by 2014.

News agency Reuters first reported that Crocker was planning to resign Monday as talks were wrapping up at the NATO summit, though the U.S. Embassy in Kabul initially denied to comment on the matter via Twitter.

Getting many calls for comment on the Reuters claim that Crocker is leaving. As a matter of policy, we do not comment on personnel issues, the embassy wrote.

The next day, however, the embassy decided to confirm the report's claim that Crocker was leaving.

Amb Crocker has confirmed with regret that he will be leaving Kabul this summer, the embassy posted on its Twitter account Tuesday morning.

In the same report, Reuters said that the deputy ambassador to Afghanistan, James Cunningham, is expected to replace Crocker, though the new appointment has yet to be confirmed. The U.S. Embassy in Kabul declined to comment on the potential appointment.

'Something None Of Us Ever Want To See Again'

In July 2011, Crocker came out of retirement after two years, at the age of 62, to serve in Afghanistan.

Crocker had been responsible for reopening the U.S. Embassy in Kabul in 2002, following the U.S.-led invasion of Afghanistan and subsequent fall of the Taliban.

Crocker has cited the terrorist attacks of Sept. 11, 2001, as the defining moment in his life that guided the later years of his career.

It's defined my life and my career basically, from that day to this. I've spent five years since 9-11 deployed in these countries, Crocker said, speaking on the 10th anniversary of the attacks in an interview with Voice of America.

I expect to be here for several more. Because, 3,000 people dead in one New York morning, is something none of us ever want to see again.

At the time of the attacks, Crocker was serving as deputy secretary of state for Near Eastern affairs under President George W. Bush. From May to August 2003, with the start of the Iraq War, he served in Baghdad as director of governance for the Coalition Provisional Authority, the Iraqi transitional government formed to take over after Saddam Hussein's ouster.

In 2004, Crocker returned to his role as an ambassador and was deployed to Pakistan for three years and later returned to the embassy in Iraq for two years before retiring in 2009, though he would return to serve in Afghanistan under President Barack Obama in 2011.