Cairo- Saudi Crown Prince Mohammad Bin Salman received a telephone call from UN Secretary-General Antonio Guterres on Tuesday to discuss progress on resolving the war in Yemen and other regional issues, Saudi Press Agency reported.

The four-year war in Yemen pits the Iranian-aligned Al Houthi movement against the legitimate, Saudi-backed government of Abd Rabbo Mansour Hadi, a conflict that has killed tens of thousands of people.

The United Nations is looking to rescue a deal struck in December between both sides to implement a troop withdrawal from Hodeida port, the main entry point for Yemen’s commercial and aid imports.

Al Houthis control Hodeida and troops of a Saudi-led coalition are massed on its outskirts. Both sides disagree over who should control the city and port after forces withdraw.

UN envoy Martin Griffiths acknowledged on Monday that proposed timelines on a pullout from the port have slipped and urged the warring parties to withdraw.

“The Secretary-General of the United Nations expressed his gratitude for the Kingdom’s support in pushing for positive results in the dialogue between the Yemeni parties,” SPA reported.

Meanwhile, Saudi soldier Mousa Awaji arrived back in the kingdom after he was released by his Al Houthi captors in Yemen. Al Houthis agreed to release him because of the poor state of his health and their inability to provide suitable care for him. His released followed efforts by coalition forces and Martin Griffith, the UN special envoy to Yemen. In return, the coalition has agreed to release seven Al Houthi detainees.

Coalition spokesman Turki Al Maliki praised Griffith and the International Committee of the Red Cross for their efforts in the release of the Saudi prisoner.

He said that Al Houthis had earlier turked a deaf ear to talks about release of prisoners. The coalition is also seeking the release of Yemeni Defence Minister Maj. Gen. Mahmoud Al Subaihi, who is being held captive by Al Houtis.