Yemen's government told the United Nations on Wednesday it would agree to a truce to end more than three months of fighting provided key "guarantees" were met, a spokesman said.
"The Yemeni authorities have informed the secretary-general of the United Nations, Ban Ki-moon, of its agreement to implement a truce in the coming days," spokesman Rajeh Badi said by phone from the government's seat of exile in Saudi Arabia.
Yemen's President Abd Rabbu Mansour Hadi, the spokesman said, "set guarantees for the success of the truce."
These included the release of prisoners by Yemen's Houthis, as well as the Houthis' withdrawal from four southern and eastern provinces where they are fighting local militias.
Houthi leader Zeifullah al-Shami said late on Wednesday that those conditions are "unacceptable" because they don't address the country's humanitarian crisis.
The fighting in Yemen pits the Houthi rebels and troops loyal to former President Ali Abdullah Saleh against southern separatists, local and tribal militias, Sunni fighters and loyalists of Hadi, who fled to Saudi Arabia amid fighting and has remained there since.
The rebels seized the capital, Sanaa, in September. In March, the Saudi-led and U.S.-backed coalition began launching airstrikes against the rebels and their allies.
On July 1, the U.N. designated the war in Yemen as a Level 3 humanitarian crisis, its most severe category.
Despite the disagreements, Shami said, the U.N.-sponsored talks that began on Sunday are continuing in Sanaa. An attempt last month at U.N.-led talks among Yemeni parties in Geneva failed to reach an agreement.
"Those conditions are actually silly from the so-called President Hadi government. Those are the same conditions that were presented at Geneva talks and now here again," Hussain al-Bukhaiti, a pro-Houthi activist, told Al Jazeera.
"I know Houthi won’t accept any condition for withdrawal, and there cannot be any precondition for cease-fire," he said.
The United Nations received a letter from the Yemeni government and was "seeking clarification from the parties," said Ban's spokesman Stephane Dujarric.
Saudi Arabia and an Arab coalition have been bombing the Iran-allied Houthis and their allies in Yemen's army in an effort to back armed opponents of the Houthis and restore Hadi.
Aid agencies say the fighting and a near blockade imposed by an alliance of Arab states aimed at weapons deliveries to the Houthis has caused a humanitarian catastrophe, with most people needing some kind of aid.
More than 3,000 people have been killed in the conflict, including 1,500 civilians, and over 1 million displaced, and the U.N. has been urgently pushing for a pause to help impoverished people.
Al Jazeera with wire services