The U.S. has abandoned its Syrian embassy for the moment, but will remain active in the region. Here's a statement from the U.S. State Department:

The United States has suspended operations of our Embassy in Damascus as of February 6. Ambassador Ford and all American personnel have now departed the country.

The recent surge in violence, including bombings in Damascus on December 23 and January 6, has raised serious concerns that our Embassy is not sufficiently protected from armed attack. We, along with several other diplomatic missions, conveyed our security concerns to the Syrian Government but the regime failed to respond adequately.

Ambassador Ford has left Damascus but he remains the United States Ambassador to Syria and its people. As the President’s representative, he will continue his work and engagement with the Syrian people as head of our Syria team in Washington. Together with other senior U.S. officials, Ambassador Ford will maintain contacts with the Syrian opposition and continue our efforts to support the peaceful political transition which the Syrian people have so bravely sought.

Read more here.