The UN said on Friday it was suspending “all official movements” in Houthi-controlled parts of Yemen after the rebel group detained a number of people employed by the world body.
The office of the resident UN co-ordinator for Yemen called for the “immediate and unconditional” release of all its detained staff held in the country.
Since the group took Yemen's capital Sanaa and ousted the internationally recognised government in 2014, the Houthis have been accused of kidnapping, arbitrarily detaining and torturing hundreds of civilians, including UN and NGO personnel.
In June, the Houthis detained 13 UN staff members, including six from the Human Rights Office, more than 50 NGO workers and a US embassy employee.
The group claimed they had uncovered “an American-Israeli spy network” operating under the guise of humanitarian organisations. The allegation was strongly rejected by the UN Human Rights Office.
In early August, the Houthis stormed the UNHCR office in Yemen, seizing keys, documents and property before returning them later that month. Two UN human rights employees were detained in November 2021 and August 2023, respectively.
The continuing detentions and incidents have heightened concerns over the safety and operations of humanitarian organisations in Yemen and the region.
The latest detentions come after US President Donald Trump issued an executive order calling for the designation of the Houthis as a foreign terrorist organisation, reversing a decision by former president Joe Biden.
Mr Trump's new Secretary of State Marco Rubio called Yemen's Prime Minister Ahmed bin Mubarak on Friday and the leaders spoke about the Houthi detentions.
"They discussed the importance of ending the Houthi threat to the Red Sea maritime security and surrounding waterways and their shared concerns regarding unlawful Houthi detentions of diplomatic, UN, and NGO staff, including current and former Yemeni staff of the US Mission to Yemen, as well as the most recent detentions of additional UN staff," State Department spokeswoman Tammy Bruce said.
The two discussed co-operation about curbing Houthi attacks and capabilities, Ms Bruce added.
Re-listing the Iran-backed Houthis will prompt a review of UN agencies and NGOs operating in Yemen that receive US funding, according to the executive order.
“Under President Trump, it is now the policy of the United States to co-operate with its regional partners to eliminate the Houthis’ capabilities and operations, deprive them of resources, and thereby end their attacks on US personnel and civilians, US partners, and maritime shipping in the Red Sea,” the White House said.
