The US says 18 of the 19 diplomatic missions recently closed due to security threats will reopen on Sunday.
The state department says its embassy in the Yemeni capital Sanaa will stay closed “because of ongoing concerns”.
The US closed 19 diplomatic missions in the Middle East and Africa last Sunday in response to what it said was a threat of a terrorist attack.
The consulate in the Pakistani city of Lahore, which closed after a separate threat, will also not reopen yet.
“We will continue to evaluate the threats to Sanaa and Lahore and make subsequent decisions about the reopening of those facilities based on that information,” said spokeswoman Jen Psaki.
“We will also continue to evaluate information about these and all of our posts and to take appropriate steps to best protect the safety of our personnel, American citizens travelling overseas, and visitors to our facilities.”
On Thursday, at least 14 suspected al-Qaeda militants – reportedly including seven from Saudi Arabia – were killed in Yemen in three drone strikes, Yemeni officials said.
The number of US strikes in Yemen has been stepped up over the past month.
Yemen is a stronghold of al-Qaeda in the Arabian Peninsula (AQAP) – an al-Qaeda offshoot considered by Washington to be the most dangerous to the West.
Staff evacuated
The US statement said the Sanaa embassy would stay closed because of concerns about a “threat stream” emanating from AQAP, without providing further details.
Most US employees at the Sanaa embassy were ordered to leave the country on Tuesday.
The embassy closures, along with a US global travel alert, came after the US reportedly intercepted al-Qaeda messages.
Reports said they were between senior figures talking about a plot against an embassy.
The US closed its consulate in Lahore on Thursday and evacuated all non-essential staff following what it described as “a credible threat”.
US officials said the evacuation was undertaken as a precaution and not related to the closure of the other diplomatic missions.
AQAP targeted
Thursday’s drone attacks in Yemen targeted a group of suspected militants, killing four of them in Wadi al-Jadd in the southern province of Hadramout, Yemeni officials told the BBC.
A day earlier, Yemen said it had foiled a major al-Qaeda plot against oil pipelines and ports.
Two strikes in Marib and Hadramout provinces killed 10 suspected militants, the security officials said, while another seven people died in a drone attack on Wednesday.
While the US has acknowledged targeting militants in Yemen with drones, it does not comment publicly on its policy or the raids.
About 30 suspected militants have been killed in a series of such raids in Yemen since 28 July, news agencies report.
On Thursday, Yemeni counter-terrorism forces raided a number of addresses north of the capital Sanaa after a tip-off that they were being used by AQAP, a Yemeni security source told BBC Arabic.
