Yemen's warring parties are expected to announce a humanitarian ceasefire within days before UN-sponsored talks to end a civil war that has killed nearly 6,000 people, an official from President Abd-Rabbu Mansour Hadi's government said on Monday.

The United Nations special envoy to Yemen has met Hadi in Aden and Houthi officials in the Omani capital Muscat with a proposed agenda for the talks, which Hadi's foreign minister Abdel-Malek al-Mekhlafi said would start on December 15.

"The Houthis have approved the agenda blueprint," an official in Hadi's office told Reuters. "Within days a humanitarian ceasefire will be declared and steps to free prisoners and lifting the siege on the cities would begin."

Forces loyal to Hadi, backed by air strikes and ground forces from a mainly Gulf Arab coalition, have been locked for nine months in a civil war with the Houthis, who rule the capital Sanaa and other cities.

The Houthi spokesman, in a posting on his Facebook page, confirmed that his group had discussed "the venue and the date for the talks planned for the middle of this month" with the UN envoy Ismail Ould Cheikh Ahmed.

"Ways for a ceasefire and subsequent confidence-building steps were also discussed, and we expressed our openness to conduct a responsible and serious dialogue," the spokesman, Mohammed Abdul-Salam, added, without providing details.

Previous UN-mediated negotiations to end the conflict through dialogue failed as battles rage across the country and Saudi-led warplanes bomb positions of the Houthi group and its Yemeni army allies.

The proposed agenda for the talks stipulates immediate confidence-building measures, including the release of the Yemeni defence minister captured by the Houthis in March, lifting a siege of cities and other population centres, and suspending recruitment of children to fight in the conflict.

Hadi's supporter say Houthi forces are besieging the city of Taiz, north of Aden. The Houthis say the Saudi-led coalition is effectively putting much of the country under siege by closing off its air space and sea ports.

The peace talks would be aimed at implementing a UN Security Council resolution adopted in April, which provides for the restoration of the Yemeni government and withdrawal of Houthi forces from the cities.-Reuters