US Secretary of State Condoleezza Rice condemned the car bombing in Syria Saturday that killed more than a dozen people, dpa reported.
"I just learned this morning of the bombing in Syria and I don't think we know" who was behind it, Rice said in New York. "Obviously, any activity by extremists is concerning."
The car bombing in Damascus killed 17 people and wounded another 14 in the early morning attack in the busy Sayyida Zainab district.
Rice said she met with her Syrian counterpart, Walid al-Moualem, on the sidelines of an Iftaar dinner in New York, where the UN General Assembly was wrapping up a week-long summit of world leaders.
The rare senior level diplomatic meeting between the United States and Syria lasted about 10 minutes, and included discussions on developments in the Middle East and the ongoing peace talks between Syria and Israel.
Rice said the United States supports the Syria-Israel talks mediated by Turkey, but added that the Israeli-Palestinian peace process remained Washington's main focus.
"We recognize that comprehensive peace has to have movement along all tracks," Rice said. "But of course, our focus is on the Palestinian-Israeli track, because we believe that that is the one that's most mature."
Syria is on the US State Department's list of state sponsors of terrorism and the United States has accused Damascus of allowing militants to cross into Iraq to carry out attacks on its soldiers.
Tension between the two countries took a turn for the worse following the assassination of former Lebanese prime minister Rafik Hariri in February 2005. Syrian intelligence was implicated in the killing, prompting Washington to recall its ambassador to Damascus.