Yemeni Ansarullah's and Oman's envoys will head to Saudi Arabia on Thursday night to try to negotiate a permanent ceasefire with Saudi officials to end the war on Yemen, two people involved in the talks said.

Ansarullah officials will travel to Riyadh with the Omani mediators, who landed in Sanaa on Thursday, the sources said.

The Saudi government and an Ansarullah spokesman did not immediately respond to requests for comment.

The trip will be the first official visit by Ansarullah officials to the Kingdom since the war on Yemen started in 2015.

The first round of the Oman-mediated consultations between Riyadh and Sanaa, which are running in parallel to UN peace efforts, was held in April when Saudi envoys visited Sanaa.

The war on Yemen has killed hundreds of thousands and left 80 percent of Yemen’s population dependent on humanitarian aid.

The Omani plane is expected to fly from Sanaa to Riyadh on Thursday night, the people said.

Sources speaking on condition of anonymity have told Reuters that the Saudi talks with Ansarullah are focused on a full reopening of ports and Sanaa airport, payment of wages for public servants from oil revenues, rebuilding efforts, and a timeline for foreign forces to quit Yemen.

The peace initiatives have gained momentum since Saudi Arabia and Iran agreed to re-establish ties in a deal brokered by China.

A permanent ceasefire in Yemen would mark a milestone in stabilizing the Middle East.