A top Yemeni official has said southern separatists backed by the United Arab Emirates should withdraw from areas they seized in the southern port city of Aden before the internationally recognised government engages in talks with them.
Deputy Foreign Minister Mohammed Abdullah al-Hadrami on Wednesday called for the Southern Transitional Council (STC) - which seeks the secession of the country's south - to hand over arms to the government of exiled President Abd-Rabbu Mansour Hadi.
Last week, the Security Belt, a militia aligned with the STC, seized government military bases, effectively wresting control of the city following four days of clashes with forces loyal to Hadi.
According to the United Nations, the fighting killed up to 40 people and wounded 260 others. But the International Committee for the Red Cross said on Monday that clinics in Aden had reported "scores dead" and hundreds wounded.
Aden has been the seat of power for Hadi's government since the Houthi rebels took over the capital, Sanaa, in 2014. The rebels also control vast swaths of Yemen's west and north.
Saudi Arabia - which leads a military coalition along with the UAE in the fight against the Houthis, in a devastating war that has been in military stalemate for years, has called for a summit over Aden without setting a date.
Abu Dhabi has echoed Riyadh's call for dialogue among Aden's warring parties but stopped short of asking the southern forces that it funds and arms to cede control.
In a meeting with Saudi Arabia's King Salman on Monday, the UAE's Crown Prince Sheikh Mohammed bin Zayed Al Nahyan called on the conflicting sides to "prioritise dialogue and reason for the interest of Yemen and its people".
The UAE, which announced recently the beginning of a troops withdrawal from Yemen, has armed and trained an estimated 90,000 allied fighters in the south.
Yemen's Washington embassy, quoting the foreign ministry, on Wednesday welcomed the Saudi initiative to address the "coup" in Aden.
But, it said in a tweet, separatists "must first commit to total withdrawal from areas forcibly seized by STC in past few days before [the] start of any talks."
The STC has voiced willingness to take part in the talks, but has not indicated that it is ready to withdraw, security sources close to the movement said.
The latest deadly clashes between the nominal allies highlighted a major rift threatening to open a new front in Yemen's long-running and multilayered conflict.
The war broke out in late 2014 when the Houthis, allied with forces loyal to former President Ali Abdullah Saleh, seized much of the country, including Sanaa.
The war escalated in March 2015 when the Saudi-UAE-led coalition launched a ferocious air campaign against the rebels in a bid to restore Hadi's government.
Since then, tens of thousands of civilians and combatants have been killed and as many as 85,000 children may have starved to death in a conflict described by the UN as the world's worst humanitarian crisis.