"But I think this, closing all of these embassies in the Middle East to North Africa, is in fact unprecedented. At least, I didn't see this during my career."
Concerns after Benghazi
House leaders have been briefed, Democratic leader Nancy Pelosi told reporters, adding that the travel alert and embassy closings provided "some understanding of the seriousness of the threat."
King, who has also heard such briefings, applauded the government's decision to close its diplomatic missions.
"I give them credit," the Republican said of the Obama administration. "I think the government is doing exactly the right thing here."
Such bipartisan agreement in Washington comes at a time when politicians are still scrutinizing the September 11, 2012, attack on the U.S. consular compound in Benghazi, which killed four Americans, including Ambassador Christopher Stevens.
Since then, Republicans have been pressing Obama's administration for answers, with some accusing officials of covering up what happened in Benghazi and not doing enough to track down the attackers.
Eight GOP lawmakers are asking that incoming FBI Director James Comey brief Congress within 30 days about the investigation. They say the administration's inquiry to date has been "simply unacceptable," according to a draft letter obtained by CNN.
Earlier last week, Vice President Joe Biden and senior State Department officials went to Congress to discuss embassy security.
Biden also briefed congressional leadership, key committee chairmen and ranking members about the latest threat concerns, a source who attended the meeting said.
Another official said the recent intelligence might not have warranted such a response before the Benghazi attack, which created a political firestorm for the administration.
On Thursday, State Department spokeswoman Marie Harf said the agency was taking the steps out of an abundance of caution.
List of closures
The following U.S. posts will be closed Monday to Friday.
U.S. Embassy Riyadh, Saudi Arabia
U.S. Consulate Dhahran, Saudi Arabia
U.S. Consulate Jeddah, Saudi Arabia
U.S. Embassy Abu Dhabi, United Arab Emirates
U.S. Consulate Dubai, United Arab Emirates
U.S. Embassy Tripoli, Libya
U.S. Embassy Amman, Jordan
U.S. Embassy Cairo, Egypt
U.S. Embassy Djibouti, Djibouti
U.S. Embassy Doha, Qatar
U.S. Embassy Khartoum, Sudan