Yemen's government has signed a power-sharing deal with separatists in the south of the country that is intended to end months of infighting.
The two are meant to be part of an alliance with a Saudi-led multinational coalition that has been battling the rebel Houthi movement since 2015.
But in August, separatists supported by the UAE seized control the city of Aden from Saudi-backed government forces.
The UN said the deal was an important step towards ending Yemen's civil war.
The conflict has devastated the country and claimed the lives of at least 7,000 civilians, according to the UN.
Monitors believe the death toll is far higher. The US-based Armed Conflict Location and Event Data Project (ACLED) said last week that it had recorded more than 100,000 fatalities, including 12,000 civilians killed in direct attacks.
The fighting has also triggered the world's worst humanitarian crisis. Four-fifths of the population - 24 million people - are in need of humanitarian assistance or protection, including 10 million who rely on food aid to survive.
Separatists seeking independence for south Yemen, which was a separate country before unification with the north in 1990, formed an uneasy alliance with President Abdrabbuh Mansour Hadi four years ago to stop the Houthis capturing Aden.
They subsequently drove the rebels out of much of the south with the help of the Saudi-led coalition, and Aden became the temporary seat of Mr Hadi's cabinet.