The UN special envoy for Yemen on Monday called on all parties to the conflict to expedite the safe return of just-released detainees by the rebels and to resume talks for the release of more detainees.

The International Committee of the Red Cross (ICRC) announced earlier Monday that 290 detainees were released unilaterally by Ansar Allah, also known as the Houthi rebels.

Stephane Dujarric, spokesman for UN Secretary-General Antonio Guterres, said Special Envoy for Yemen Martin Griffiths welcomed the initiative and "called for all parties to ensure the safe return of the released detainees to their homes."

Griffiths expressed his hope that the release will lead to further initiatives that will facilitate the exchange of all conflict-related detainees in accordance with the Stockholm Agreement, said Dujarric, referring to the December 2018 intra-Yemen accord.

"The special envoy called on the parties to work together to expedite the release, transfer and repatriation of conflict-related detainees and invited the parties to meet at the nearest opportunity, so as to resume discussions on future exchange as per their commitments in the Stockholm Agreement," the spokesman said.

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Yemen's Houthis unilaterally release hundreds of detainees

The Iran-aligned Houthis agreed in Sweden in December with Yemen's Saudi-backed government to swap prisoners as a confidence-building step. But the arrangement has been stalled as the sides struggled to agree on implementation. Each side was meant to release around 7,000 prisoners.

The conflict has killed tens of thousands of people and pushed millions to the brink of famine. The United Nations calls it the world's worst humanitarian crisis.