Syrian Foreign Minister Walid al-Moallem is to undergo heart surgery at a hospital in Lebanon.

Syrian Foreign Minister Walid al-Moallem is to undergo heart surgery at a hospital in Lebanon, medical sources said on Friday.

Moallem, 73, was admitted to the American University of Beirut Medical Center on Thursday, where coronary tests showed he needed an operation, the sources told Reuters. They did not say when the surgery would take place.

Moallem, Syria's top diplomat since 2006, led the Syrian official government delegation to peace negotiations in Geneva-II with representatives of the opposition.

Two rounds of peace talks mediated by U.N. peace mediator Lakhdar Brahimi in January and February failed to bring the sides closer to agreement on a transitional government or halt fighting that has killed more than 146,000 people since the conflict started in March 2011.