Saudi Arabia and the UAE have called on Yemeni government fighters and southern secessionists to focus their efforts on fighting Houthi rebels, in an apparent attempt to end a standoff between the two sides in Aden.

Emirati-backed separatists took over large parts of the southern port city earlier this week, including military bases, but stopped short of advancing on the presidential palace after clashing with pro-government forces and briefly surrounding the building while Prime Minister Ahmed bin Daghr and his ministers were inside.

The move exposed potential divides between Saudi Arabia, which finances and arms the Yemeni government, and the UAE, which is providing direct financial and military aid to the separatist Southern Transitional Council and its armed militia.

Yemeni government officials accused the Emirati government of deploying fighter planes to help the separatist fighters.

In a statement published by the Saudi Press Agency on Thursday, the Saudi-led coalition said Riyadh and Abu Dhabi shared "one goal and a shared vision for Yemen".

"Saudi Arabia and the UAE have no ambitions but for Yemen to be a safe, stable, and able, Arab nation," the statement said.

While stopping short of expressing support for the Yemeni government, which is based in Aden because the capital is under Houthi rebel control, the coalition called on both sides to focus on the goal of "defeating the Houthi militias of Iran."

The separatists want greater autonomy for South Yemen, which was an independent state until reunification with the north in 1990.

They complain that the government has presided over rampant corruption and neglected southern regions.

The fighting in Aden has left at least 36 people dead and wounded more than 185 people since Sunday, according to the International Committee of the Red Cross.

Arab coalition intervention

The UAE and Saudi Arabia intervened militarily in Yemen in March 2015 after Houthi rebels swept across the country and threatened to conquer the last government stronghold of Aden.

While the coalition and government fighters successfully fended off the Houthi takeover of Aden, years of air attacks have failed to dislodge the Houthis from much of the rest of the country.

The coalition's stated aim of restoring President Abd-Rabbu Mansour Hadi's rule still seems distant, as the capital Sanaa remains under Houthi control.

The Saudis have indicated they want out of the war and have largely limited their campaign to bombing raids, but the Emiratis have also committed troops to the effort to defeat the Houthis.

Separatists, government forces, and the Houthis, are competing for control over Yemeni territory alongside al-Qaeda and the local affiliate of the Islamic State of Iraq and the Levant (ISIL, also known as ISIS) group.

The war has severely damaged the country's infrastructure with the UN warning that up to 8 million people are at risk of starvation and more than a million have contracted cholera.