Clashes between rebels and pro-government forces and Saudi-led air strikes killed at least 85 people in Yemen, medics and military sources said Sunday, after Riyadh pledged to fund a UN aid appeal.
The United Nations says hundreds of people have died and thousands of families have fled their homes since the coalition air war began on March 26 at the request of embattled President Abedrabbo Mansour Hadi.
Since Saturday, fighting has concentrated on four key southern cities, while Saudi-led warplanes also pounded Huthi rebel positions in the area.
The deadliest clashes took place in the city of Daleh, where 31 Huthis and 17 pro-Hadi forces were killed on Sunday, a local official said, also reporting a series of air strikes on rebel positions.
Pre-dawn clashes in the southwestern city of Taez left 10 Huthi rebels and four pro-Hadi militiamen dead, medics and local sources said.
Taez, Yemen's third largest city after the capital Sanaa and second city Aden in the south, has seen fierce clashes over the past week, after having been largely spared in fighting that has spread across several provinces.
On Sunday, coalition warplanes pounded Huthi positions in Taez, an AFP correspondent said, adding that the streets were empty and shops were closed.
Seven more Huthis were killed in an attack by tribesmen in the southern province of Shabwa.
In Aden, 11 Huthis and five pro-Hadi fighters were killed on Saturday night and Sunday morning, military sources said.
The pro-Hadi fighters recaptured the Russian consulate and a Hadi residence from the Huthis, they added.
The rebels, who seized Sanaa unopposed in September, have since expanded their control across the impoverished Arabian Peninsula country.
Saudi King Salman ordered the aid pledge following a UN appeal on Friday for $274 million (253 million euros) in emergency assistance for the millions affected by Yemen's multi-sided conflict.
UN Humanitarian Coordinator Johannes Van Der Klaauw had said that "ordinary families are struggling to access healthcare, water, food and fuel -- basic requirements for their survival".
Aid has only trickled in to Yemen, largely because of Saudi-led coalition restrictions on its airspace and ports.
On Saturday, the spokesman for the Saudi-led coalition said efforts are under way to step up aid after two loads of supplies donated by Qatar and the United Arab Emirates reached Yemen.
"Other cargos will follow in the coming days" in a "sea bridge to get aid to the Yemeni people," Brigadier General Ahmed al-Assiri told reporters in Riyadh.
He insisted, however, that shipments must be coordinated with the coalition.
Aid group Doctors Without Borders said "more than 70 tonnes of medical material" arrived by plane in Sanaa on Saturday.
The UN agency for refugees says that up to 150,000 people have been displaced over the past three weeks, while more than 300,000 had already fled their homes because of unrest in past years.
The coalition has launched more than 2,000 air strikes on Yemen since its campaign began, Assiri said.
The Huthis swept into the capital in September from their highland stronghold and later advanced south on the major port of Aden, forcing Hadi to flee to Riyadh.
Sunni-ruled Saudi Arabia fears the Huthis would shift Yemen into the orbit of its Shiite rival Iran.
Though a key ally of the Huthis, Iran denies arming the Shiite rebels who have allied with army units loyal to Ali Abdullah Saleh, the president forced out in Yemen's 2011 uprising.
On Friday, Tehran submitted a four-point Yemen peace plan to UN chief Ban Ki-moon -- namely calling for a ceasefire, the resumption of political talks and the formation of a unity government.
Al-Qaeda, which appears to have been spared the wrath of the coalition, has exploited the air war on the Huthis to expand its influence in Yemen.
On Friday it overran an army camp in the southern province of Hadramawt, a day after seizing the airport in provincial capital Mukalla.
On Saturday night, a US drone killed three Al-Qaeda suspects when it targeted a vehicle in Saeed in Shabwa province, a tribal chief said.