A handout picture provided by the Saudi Royal Palace on Tuesday shows Yemeni Southern Transitional Council (STC) member and former Aden governor Nasser al-Khabji, and Yemen's deputy prime minister Salem al-Khanbashi, sign documents during a peace-signing ceremony. — AFP Photo

RIYADH — Yemen's internationally recognized government signed a power-sharing deal with southern separatists on Tuesday, in a Saudi-brokered initiative to end a conflict simmering within the country's civil war.

Unrest in the south, which saw secessionist forces seize control of Yemen's interim capital Aden, distracted the Saudi-led coalition from its battle against Iran-backed Huthi rebels and raised fears the country could fall apart entirely.

The so-called Riyadh agreement, hailed as a stepping stone towards ending the wider conflict, would see the government's return to Aden and the formation of a new cabinet of 24 ministers with equal representation for southerners, including the separatist Southern Transitional Council (STC).

The agreement, seen by AFP, would also place armed forces from both sides under the authority of the defence and interior ministries.

"This agreement will open a new period of stability in Yemen. The kingdom of Saudi Arabia stands with you," Saudi Crown Prince Mohammed bin Salman said at a signing ceremony in Riyadh aired on state television.

The deal also drew praise from US President Donald Trump, who tweeted: "A very good start! Please all work hard to get a final deal."

- 'Important step' -

The United Nations special envoy for Yemen, Martin Griffiths, said the deal would propel efforts to end the wider civil war that has devastated the country.

"The signing of this agreement is an important step for our collective efforts to advance a peaceful settlement to the conflict in Yemen," he said in a statement.

"Listening to southern stakeholders is important to the political efforts to achieve peace in the country."

In August, the STC-dominated Security Belt Forces took control of Aden, which had served as the beleaguered government's base since it was ousted from the capital Sanaa by Huthi rebels in 2014.

The south was an independent state before being forcibly unified in 1990 and the STC has said it wants to regain its lost status.

The deadly bout of fighting in Yemen's already convoluted conflict pitted Saudi-backed government forces against the UAE-trained Security Belt Forces -- both allied against the Huthis -- raising fears the country could split apart with disastrous effects.

"In the short term, the agreement will allow the coalition to stick together and focus their efforts on fighting the Huthis instead of each other," said Elisabeth Kendall, senior research fellow at Oxford University.

"In the long term, it simply kicks the can down the road on southern secession. Southern ambitions won't just go away. The question is, can they be temporarily reined in."

Both Yemen's President Abedrabbo Mansour Hadi and STC leader Aidarous al-Zoubeidi attended the ceremony in Riyadh, along with Abu Dhabi's powerful Crown Prince Mohammed bin Zayed Al-Nahyan.

The warring factions in recent weeks held indirect talks mediated by Saudi Arabia in the kingdom's western city of Jeddah, which culminated in the deal signed in Riyadh.

In a bid to defuse tensions, the UAE last month handed over to Saudi forces key positions in Aden, including an airbase and the international airport.

- Mistrust abounds -

The fighting had exposed simmering divisions between Saudi Arabia and the UAE, leading members of the coalition that intervened in Yemen in 2015 as the Huthi rebels closed in on Aden, prompting Hadi to flee into Saudi exile.

The mistrust between the allies has posed a headache for regional powerhouse Saudi Arabia, which remains focused on fighting the Huthis, who are aligned with Riyadh's archfoe Iran.

Nevertheless, Abu Dhabi's crown prince tweeted a picture of himself and Prince Mohammed walking hand in hand with Hadi after Tuesday's ceremony.

Mohammed al-Jaber, the Saudi ambassador to Yemen, said Tuesday's agreement will send a "strong message" to the Huthis to come to the negotiating table, paving the way to end the war.

Over four years the conflict has killed tens of thousands of people, most of them civilians, and driven millions more to the brink of famine, in what the UN calls the world's worst humanitarian crisis.

The Huthis have offered to halt all attacks on Saudi Arabia as part of a wider peace initiative, later repeating their proposal despite continued air strikes from the Saudi-led coalition.

The offer came after the Huthis claimed responsibility for attacks on September 14 against two key Saudi oil installations that temporarily knocked out half of the OPEC giant's production.

Riyadh and Washington, however, blamed Iran for the attacks -- a charge denied by Tehran. — AFP