Senior US envoy Jeffrey Feltman said he held "constructive" talks on Thursday with Syrian Foreign Minister Walid Muallem, on his second visit in two months to try to improve ties with Damascus.
"We noted in our discussions improvement in our ability to work bilaterally with the Syrians since our last visit here two months ago," said Feltman, acting secretary of state for Near Eastern affairs.
"I would describe our meeting today as constructive," he told reporters after talks with Muallem, and vowed to pursue dialogue.
Feltman is on his second visit to Damascus since US President Barack Obama took office in January pledging to engage with all Middle Eastern countries, including Washington's foes such as Syria and Iran.
"To be sure, Syria and United States share some mutual interests. Syria and United States also have some differences in our points of view on certain important issues," Feltman said.
"We came here today as part of President Obama commitment's to use diplomacy and to use dialogue in order to try to see where we can move forward, where our interests overlap, and to see where we can try and work together to bridge the differences that remain in some of our policies."
The talks come just two days after a visit to Damascus by Iranian President Mahmoud Ahmadinejad, whose country is Syria's closest regional ally but at loggerheads with West over its nuclear drive.
Obama has also offered an olive branch to Tehran and a US Senate report out on Thursday insists that US engagement with Iran must convince Tehran to halt progress in its ability to build a nuclear bomb and accept tough international controls.
"This is a time when US intentions towards Syria will be put to the test," Muallem told reporters before the meeting.
Feltman, who is accompanied by National Security Council Senior Director Daniel Shapiro, said: "We look forward to continue the dialogue here and in Washington."
He also reiterated Washington's readiness to help push for progress in the Middle East peace process.
"We also conveyed, on behalf of the US administration... President Obama's sincere commitment to pursue Arab-Israeli peace on all tracks," he said.
Syria and Israel engaged in indirect Turkish-sponsored peace talks last year following an eight-year hiatus, but they were suspended after Israel's war on the Gaza Strip in December-January.
Syrian President Bashar al-Assad said in March that his country could hold direct peace talks with Israel if the United States acted as an arbitrator.
Ties between Washington and Damascus became strained after the US-led invasion of Iraq in 2003, and the assassination of Lebanese leader Rafiq Hariri in 2005 which was blamed on Syria. Damascus denied any involvement.
Washington recalled its ambassador in February 2005 following Hariri's murder and Feltman's visit in March was the first high-level US trip to Damascus since then.
The United States accuses Syria and its non-Arab ally Iran of giving material support to Hamas and Hezbollah in their conflicts with Israel.
It also charges that Syria has turned a blind eye to Islamist militants entering Iraq through its border, while also accusing Iran of actively supporting anti-US militants in Iraq.