Mitchell reaffirmed President Barack Obama and Secretary of State Hillary Clinton's commitment "to a comprehensive peace in the Middle East that includes peace between Israel and Palestinians, Israel and Syria, Israel and Lebanon.
"It also includes the full normalisation of the relations between Israel and the Arab states," he said after arriving in Damascus from talks with Lebanese President Michel Sleiman in Beirut, where he pressed home the same message.
"Syria certainly has an important role to play in all these efforts," he told reporters on his third visit to the country since being appointed Obama's special envoy to the Middle East.
Mitchell is also due to meet Israeli and Palestinian leaders on his trip as Washington strives to revive long-stalled peace talks, stymied when Israel launched an offensive on the Islamist-ruled Gaza Strip in December 2008.
"This is my third meeting with the president and I look forward to build on the positive relationship we have to make tangible progress on our efforts to peace and on a bilateral relationship between US and Syria," he said.
Since Obama came to office exactly one year ago, official visits to Syria by US officials have multiplied as Washington believes Damascus can also help with issued relating to Iraq and Lebanon.
Mitchell's latest tour comes less than a week after Obama's national security adviser James Jones met Palestinian and Israeli leaders aimed at furthering US-led peace efforts.
The Palestinians say they will not resume talks until Israel halts all settlement building in the occupied territories.
Source: AFP Global Edition