UN envoy Martin Griffiths on Tuesday was preparing to head to war-torn Yemen to lay the groundwork for peace talks in Sweden, after fresh fighting shook the flashpoint city of Hudaida.
Griffiths, whose efforts at kickstarting peace talks failed in September, is again trying to get the Houthis and the Saudi-backed government to the negotiating table by the end of the year.
He is expected to meet with Houthi officials in the capital Sanaa on Wednesday.
Both sides have in the past week expressed their support for the envoy and his mission to hold talks in Stockholm, but fierce clashes erupted in the Red Sea city of Hudaida late on Monday after a lull.
Military officials said that the battles were the worst since loyalists halted an offensive last week, and were concentrated in the eastern part of the city where rebels fired artillery.
Pro-government forces struck back, supported by warplanes from the Saudi-led coalition which launched a dozen raids, the sources said.
According to Houthi-run media, clashes lasted up to four hours and resulted in fatalities.
The city was relatively calm on Tuesday morning, according to sources on the ground.
Call for truce
On Monday, Britain presented to the UN Security Council a draft resolution urging an immediate truce in Hudaida city, whose port serves as an entry point to nearly all imports and humanitarian aid to the impoverished country.
The draft, circulated by Britain to the 14 other council members, sets a two-week deadline for the warring sides to remove all barriers to humanitarian aid.
The proposed resolution would significantly ratchet up pressure on the Saudi-led coalition and the Houthis to seek a negotiated settlement in Yemen, where millions are on the brink of starvation.
It also calls for a large injection of foreign currency into the economy to support Yemen's collapsing currency and for salaries of civil servants, teachers, and health workers to be paid within a month.
Mohammed Ali al Houthi, head of the Houthi rebels' Higher Revolutionary Committee and an influential political figure, tweeted on Monday that he wanted his group to announce "readiness to suspend and halt all military operations" and stop firing missiles on Saudi Arabia.
Saudi Arabia also lent its support to new talks.
Saudi King Salman told the Shura Council, his country's top advisory body, that Riyadh also backed a "political solution" and a "comprehensive national dialogue" in Yemen.
Multiple past attempts to hold negotiations between the government alliance and Houthis have failed.
Griffiths said on Monday he hoped the rivals would meet in Sweden "within the next few weeks."
No date has been set as of yet.
'Stop selling weapons'
The Houthis have controlled Yemen's capital Sanaa since capturing it in late 2014, when they also took control of Hudaida and its port.
A year later, Saudi Arabia and its allies intervened in the war to bolster Yemeni President Abd Rabbu Mansour Hadi.
Both parties in the Yemen conflict stand accused of acts that could amount to war crimes.
Human Rights Watch on Tuesday called on France to address laws-of-war violations with the UAE, a key member of the Saudi-led coalition, during Crown Prince Mohammed bin Zayed al Nahyan's visit to Paris on November 21.
"If President [Emmanuel] Macron is truly concerned about the humanitarian crisis in Yemen, he should tell the crown prince that France will stop selling weapons to the UAE if there's a real risk of their unlawful use," said Benedicte Jeannerod, France director at Human Rights Watch.
Father who lost four children calls for end to bloodshed
A Yemeni father who lost four children in renewed clashes in Hudaida has pleaded for end to bloodshed.
''This was the result of the crime. Three of my girls became martyrs at the same time, and another three were wounded, including Naziha, who is severely wounded and has had to be moved al Thawra hospital where she's being treated for torn intestines,'' said father of victims, Maged Ghaleb.
His fourth child died on the way to the hospital.
"We are calling on all the honorable people of the world, all people, from all religions, anyone who has a heart; to stop this bloodshed. We cannot take it. Yemenis and their children are being murdered in cold blood.''
Although western governments have condemned civilian deaths in Yemen, they remain political and military backers of Saudi Arabia, which is a regional ally and spends billions of dollars on arms from the United States, Britain and France.
The World Health Organization says nearly 10,000 people, mostly civilians, have been killed in Yemen since the Saudi intervention in March 2015, but rights groups believe the toll may be five times higher.
The war in Yemen, already one of the world's most impoverished countries, has left the nation on the edge of mass starvation.