Britain said Tuesday it had withdrawn all staff from its embassy in Yemen, after the United States ordered its citizens to leave the country following a worldwide terror alert.
"Due to increased security concerns, all staff in our Yemen embassy have been temporarily withdrawn, and the embassy will remain closed until staff are able to return," a Foreign Office spokesman said.
Britain was among several Western countries to close their embassies at the weekend following US warnings of an Al-Qaeda attack. Britain had also withdrawn some staff.
In a fresh alert on Tuesday, the United States ordered Americans to leave Yemen immediately and withdrew all non-essential US government staff.
The alert was reportedly linked to the interception of communications between Al-Qaeda leader Ayman al-Zawahiri and the leader of the group's Yemen-based affiliate, Nasser al-Wuhayshi.
London originally closed its embassy in Sanaa just for Sunday and Monday, but on Monday said it would extend the closure until the end of the Muslim festival of Eid later this week.
After Washington closed some two dozen embassies and consulates on Sunday, it said that some 19 diplomatic posts in the Middle East and Africa will remain shut until August 10.
The British government advises its citizens against travelling to Yemen and on its website "strongly urges" British nationals to leave immediately.