"The Department of State alerts U.S. citizens to the continued potential for terrorist attacks, particularly in the Middle East and North Africa, and possibly occurring in or emanating from the Arabian Peninsula," the alert posted on the State Department's Consular Affairs Facebook page said. "Current information suggests that al-Qaida and affiliated organizations continue to plan terrorist attacks both in the region and beyond, and that they may focus efforts to conduct attacks in the period between now and the end of August."
The travel alert expires Aug. 31.
Because terrorists can attack at different venues and use a variety of weapons, "U.S. citizens should take every precaution to be aware of their surroundings and to adopt appropriate safety measures to protect themselves when traveling," the alert said.
The warning came as officials announced the United States was working with foreign intelligence agencies to try to learn more about the potential target of a suspected al-Qaida-linked plot to attack any of the 284 American diplomatic posts around the world, NBC News reported.
Embassies and consulates normally open on Sundays are closing this weekend because of the potential threat, officials said. Closures so far include the diplomatic missions in Cairo, Tel Aviv, Riyadh, Baghdad, Kabul, Bahrain and dozens of other embassies and consulates.
A State Department official told NBC News the closures could be extended, "depending on our analysis."