US Secretary of State John Kerry expressed the hope in Saudi Arabia on Sunday that a new ceasefire in the Yemen conflict could be agreed within two weeks.
On his last visit to the kingdom as secretary, Kerry said the United States will work with Britain, the United Arab Emirates and Saudi Arabia to achieve a new pause in the fighting, which would be the eighth ceasefire attempt since hostilities escalated early last year.
The group of four nations, formed previously to focus on Yemen, "hopes that within two weeks it might be possible to achieve" a pause in fighting, Kerry told reporters at a joint news conference with his Saudi counterpart Adel al-Jubeir.
"The failure to achieve a lasting cessation of hostilities is disturbing to all of us," Kerry said.
Since March 2015, Saudi Arabia has led an Arab coalition conducting air strikes against Huthi rebels and providing other assistance to local forces in support of President Abedrabbo Mansour Hadi.
The coalition intervened after the Huthi rebels allied with elite members of security forces loyal to Yemen's former president Ali Abdullah Saleh seized the capital Sanaa and overran other parts of the country.
Previous ceasefire attempts collapsed when new fighting broke out.
The group of four nations -- which also met Oman's foreign minister as well as UN envoy Ismail Ould Cheikh Ahmed -- reaffirmed UN proposals for a peace "roadmap" made in October.
Sources have said the plan calls for agreement on naming a new vice president after the rebels withdraw from Sanaa and other cities, and hand over heavy weapons to a third party.
Hadi would then transfer power to the vice president who would appoint a new premier to form a government in which the north and south of Yemen would have equal representation.
Hadi, who has spent most of his time in Riyadh since early last year, rejects the plan, however, saying that he would only cede power to an "elected" leader.
The rebels, in turn, in late November formed a 42-member government of "national salvation" in areas they control.
Ould Cheikh Ahmed called the rebels' move an obstacle to the peace process.
Riyadh and Washington accuse Iran of arming the Huthis, a charge Tehran denies.
Since early last year the war in Yemen has killed more than 7,000 people, about half of them civilians, while the humanitarian situation is "dire and deteriorating rapidly", according to Kerry.
Washington's top diplomat leaves office in January at the end of President Barack Obama's presidency.
But he said the US will "remain engaged" in the search for peace in Yemen.
"We think we've found a path that can move forward," Kerry said.
"And we invite the parties, President Hadi, the Huthis and their supporters, both sides, to take advantage of this moment".
He added that Iran has also indicated that it wants an end to the Yemen war, "and they believe that the key is for Huthis to be able to have some role within government".
Yemen's Tourism Minister Mohamed Qubaty told reporters that Kerry is a "lame duck" attempting "a shot from across 50 yards to score a goal at the last minute."
The Saudi-led coalition has faced repeated allegations of killing civilians during its air strikes in Yemen, and last week the United States blocked the transfer of precision-guided bomb kits to Saudi Arabia.
A senior US administration official said the move reflected "strong concerns with the flaws in the coalition's targeting practices" and its overall conduct of the Yemen air war.
At Sunday's news conference Jubeir dismissed such reports as "media propaganda" and said the Saudi-led coalition had not been contacted about a halt in shipments.