The State Department warned travelers of a world-wide threat of a terrorist attack Friday, one day after announcing plans to shut down U.S. embassies and diplomatic posts across the Middle East, Northern Africa and Central Asia.

The alert said U.S. citizens should be aware of the “continued potential” of terrorist attacks by al Qaeda and affiliated organizations in the Arabian Peninsula. The warning says U.S. officials are particularly concerned about the potential of assaults taking place in the Middle East and North Africa between now and the end of August.

Al Qaeda in the Arabian Peninsula (AQAP) is based in Yemen, where the U.S. launched three strikes in the past week in remote areas of the country thought to be AQAP hideouts.

The strikes are the first this month, and Yemeni media reported that at least five alleged members of al Qaeda were killed. Just a few months ago, AQAP acknowledged that one of their leaders, an expert in bombing technology, died from wounds he first received in a U.S. missile strike in Yemen last year.

It is not known whether the specific terrorist threat that prompted the world-wide travel warning, as well as the embassies' closing, is related to the U.S. strikes or to the end of Ramadan, Islam's holy month, which ends Aug. 7.

 “Current information suggests that al Qaeda and affiliated organization 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 State Department alert said.

Terrorists could use a “variety of means and weapons” and target both “official and private interests,” the alert warns. “U.S. citizens are reminded of the potential for terrorists to attack public transportation systems and other tourist infrastructure.”

The State Department on Thursday announced plans to close numerous embassies in Muslim countries in response to heightened security threats.

State Department spokeswoman Marie Harf said Thursday that the move is "precautionary," and was made “out of an abundance of caution and care for our employees and others who may be visiting our installations.”

Earlier Friday, ABC News reported that U.S. intelligence agencies are reacting to a “credible and serious security threat,” and that embassies set to be closed include those in Egypt, Afghanistan, Iraq, Saudi Arabia, Dubai, Qatar, Bahrain and Kuwait, Bangladesh, Jordan, Oman, Algeria, United Arab Emirates, Yemen and Libya.

Once the posts are closed Sunday, the State Department will assess what security threats exist and weigh how long to keep the facilities shuttered.

“It is possible we may have additional days of closing as well,” Harf said.

The threat warnings came after Vice President Joe Biden met with a bipartisan group of lawmakers on Capitol Hill to discuss security lapses at U.S. diplomatic posts around the world and to address lawmakers’ concerns that the facilities could be vulnerable to deadly attacks like the one in Benghazi, Libya, last year that left a U.S. ambassador and three others dead.

“We’ve got decisions that have to be made about embassies and consulates, and [the administration] wants to consult with us on it," said Sen. John McCain, R-Ariz. "It’s a serious issue.”

House Foreign Affairs Committee Chairman Ed Royce, R-Calif., said the closings were not mentioned during Wednesday's meeting with Biden even though it was directly related to issues they were discussing.

“The issue is embassy security and how we can make certain that the mistakes that occurred before the attack in Benghazi don’t happen again,” Royce told the Washington Examiner.

Royce singled out the State Department’s reliance on a local Libyan militia to help protect the Benghazi post. Just before the attack occurred, that local militia left.

“We want to make sure we hire guards that will give the best value,” he said.

A State Department's inspector general's report made public last week directly criticizes the Bureau of Diplomatic Security for failing to perform a physical inspection before approving the security plan for an embassy in Kabul, Afghanistan, which was the target of a bold attack by Taliban insurgents two years ago.

Royce would not comment on the inspector general’s report, saying only: “We are aware of the threat environment in Central Asia.”

Just hours before the State Department's announced embassy closings Thursday, Royce's committee approved legislation that would provide $4.8 billion for embassy security, including the construction of new facilities and upgrades like blast-resistant doors and windows to existing buildings.

The legislation also calls for an increased Marines presence at embassies and enhanced planning for the rapid deployment of military personnel to a crisis area. The hiring of local security guards would still be allowed, but officials would be encouraged to hire those that provide the "best value" and not just the cheapest help available.

“Some of the steps would go a long way in strengthening the embassies most at risk,” Royce said.

Over August, House Foreign Relations Committee staffers will travel to a number of the embassies most at risk, Royce said, although he declined to specify which ones.

The additional attention to the embassies and consulates comes as Republican lawmakers press an investigation into the Sept. 11, 2012 terrorist attack in Benghzai. Lawmakers have accused the Obama administration of misleading the public about the nature of the attack just ahead of the November presidential election.

House Oversight and Government Reform Committee Chairman Darrell Issa, R-Calif., on Thursday issued two subpoenas for State Department documents related to a previous investigation of the Benghazi attacks, conducted by the independent Accountability Review Board.