An top aide to George Mitchell, President Barack Obama's Mideast envoy, held talks with Syrian Foreign Minister Walid al-Moallem on Thursday in Damascus, in what could potentially be a bid to revive stalled peace talks between Syria and Israel.
Fred Hof refused to speak to reporters after his 90-minute meeting with the Syrian foreign minister.
Hoff met earlier this week with officials in Israel.
Syria has insisted that the promise of an Israeli withdrawal from the Golan Heights be a precursor to any renewed peace negotiations between the two countries. Prime Minister Binyamin Netanyahu has vehemently rejected the notion of a withdrawal.