Yemen`s Huthi rebels have ordered all US and British staff of the United Nations and its agencies to leave the country within a month, a UN official told AFP.
In a letter dated January 20 and shared on social media, the authorities in the Huthi-controlled capital Sanaa told the UN resident coordinator that employees with British and US nationality had one month to "prepare to leave the country".
"They must be ready to leave as soon as the deadline expires," the document said, adding that 24 hours` notice would be given by letter.
While they only control a fraction of Yemen`s territory, the Huthis hold sway over most of the country`s population centres.
A UN official confirmed to AFP that they had received the memo.
"The UN and its partners have taken note of this and are waiting to see what are the next steps," said the official, who asked to remain anonymous.
Peter Hawkins, the UN`s humanitarian coordinator in Yemen, is himself British.
The expulsion followed joint strikes by the United States and Britain against the Huthis aimed at ending the group`s attacks on commercial shipping in the Red Sea and Gulf of Aden, threatening global trade.
The United States has launched multiple further strikes and on Tuesday carried out a second set of joint strikes with Britain.
Last week, Washington redesignated the Huthis a "global terrorist group", having lifted it in 2021 to ease aid delivery to the impoverished country.
The Huthis have fought a nearly decade-long civil war against government forces, who are backed by Saudi Arabia.
The conflict plunged Yemen, by far the poorest country on the Arabian Peninsula, into a deep humanitarian crisis, labelled among the worst in the world by the UN.
Since mid-November, the rebels have launched missiles and drones from Yemen`s coast aimed at shipping the group says is linked to Israel, in solidarity with the Palestinians in Gaza.
Gaza is under siege by Israel, which aims to destroy Hamas after the militant group`s surprise attack of October 7.
The Huthis have reacted to the US and British strikes with defiance, targeting further ships.
The United States, Israel`s major ally and provider of military equipment, has created an international coalition to patrol the Red Sea and protect commercial traffic.