The United Nations announced the suspension Monday of its activities in Yemen's Saada region, a Huthi stronghold, after the rebels detained multiple personnel there this year.
The Iran-backed Huthis have arrested dozens of staffers from UN and other humanitarian organizations, most of them since the middle of 2024, as Yemen's decade-long civil war grinds on.
In January alone the rebels detained eight UN workers, including six in Saada.
As a result, the UN secretary-general "has instructed the agencies, funds and programmes of the United Nations, in the absence of the necessary security conditions and guarantees, to pause all operations and programmes" in Saada, deputy spokesman Farhan Haq said.
"This extraordinary and temporary measure seeks to balance the imperative to stay and deliver with the need to have the safety and security of the UN personnel and its partners guaranteed," he said.
The pause is intended to " give time to the de facto authorities and the United Nations to arrange the release of arbitrarily detained UN personnel and ensure that the necessary conditions are in place to deliver critical humanitarian support," he added.
Haq was unable to say how many Yemenis would be affected by the pause in UN activities.
In late January, the UN announced that the Huthis had detained seven staff members -- a number that has now been revised to eight, and which adds to the dozens of NGO and UN personnel detained since June.
The Huthis claimed the June arrests included "an American-Israeli spy network" operating under the cover of humanitarian organizations -- allegations emphatically rejected by the UN Human Rights Office.
The Huthis' seizure of the capital Sanaa in September 2014 prompted a Saudi-led intervention the following March in a war that has now killed hundreds of thousands of people as a result of both direct and indirect causes, such as disease.