Yemen war: Fighting rages over vital port of Hudaydah
Fierce fighting has been reported after pro-government forces in Yemen, backed by a Saudi-led coalition, launched an offensive on the rebel-held city of Hudaydah, a key port for aid supplies.
Thirty Houthi rebels and nine members of pro-government forces are said to have been killed.
Coalition forces are now within two kilometres of the city's airport, the Emirati envoy to the UN says.
The UN Security Council restated its fears about the fate of civilians.
The emergency meeting on Thursday, called by the UK, saw members agree the port must be kept open to prevent a further worsening of Yemen's humanitarian crisis.
About eight million people are at risk of starvation in the war-torn country and the coastal city is where most aid arrives for people in rebel-held areas.
However, there was not enough support on the council for Sweden's motion to demand an immediate halt to the offensive on Hudaydah.
Vassily Nebenzia, Russia's UN ambassador and president of the council in June, said the body urged "all sides to uphold their obligations under international humanitarian law".
Learn more about Yemen's war
- Calm before storm in Hudaydah
- Yemen's conflict in 400 words
- Why this battle matters
- Who is fighting whom?
The Emirati news agency Wam said attacking forces had managed to "liberate areas... in the surroundings of the airport" and captured or killed "dozens" of Iranian-backed Houthis.
It reported the "martyrdom" of four Emirati soldiers but did not give further details of the fighting.
Medical sources in the region said early on Thursday that 22 Houthi fighters had been killed in coalition strikes.
Houthi rebels, meanwhile, said they had struck a coalition warship with missiles, although there was no confirmation of this.
The rebels also reported that they had successfully launched a missile towards the southern Saudi city of Khamis Mushait, although Saudi-owned Al-Arabiya TV said that Saudi air defences destroyed the weapon.
The Hudaydah offensive, which analysts say could be the biggest battle so far in the Yemeni civil war, has raised fears of mass casualties among the city's population of 600,000 people.
However, coalition spokesman Col Turki al-Malki said they wanted to avoid a street war with the Houthis "for the safety of civilians".
He told al-Hadath TV that the aims were to win control of the airport and seaport as well as the main road leading to the capital, Sanaa.
The pro-government assault began after Houthi rebels ignored a deadline to withdraw.
Separately on Thursday, pro-Yemeni government media reported that President Abdrabbuh Mansour Hadi and other senior officials had returned to the temporary capital of Aden.
The government has spent much of its time in neighbouring Saudi Arabia since Houthi rebels seized control of Sanaa and other areas in the north-west of the country in late 2014.
Alarmed by the rise of a group they saw as an Iranian Shia Muslim proxy, Saudi Arabia and eight other Sunni Arab states launched a military campaign in March 2015 to restore Mr Hadi's government.