The US will close a number of embassies and consulates, mostly in the Middle East, on Sunday in response to an unspecified threat.
A state department spokeswoman said the order applied to any embassy or consulate normally open on Sunday.
In the Muslim world, Sunday is a work day. In other parts of the world US diplomatic offices are shut on Sunday.
Last year on 11th September, the US consulate in Benghazi, Libya, was attacked, leaving four Americans dead.