Almost 10,000 civilians have been killed in the conflict so far, according to the World Health Organisation.
The United Nations says about 14 million people, or half Yemen's population, could soon be on the brink of starvation in a man-made disaster.
The UN appeal came just a few days after the U.S., in a significant shift, exerted pressure on Riyadh, a close ally, to end the aggression against the Yemenis by calling for a truce and peace talks.
The port city of Hodeida, which is in the hands of Houthis rebels, is since Thursday, heavy fighting theater and the target of air strikes by pro-government forces supported by the coalition led by Saudi Arabia.
United Nations chief Antonio Guterres has demanded an "immediate" halt to fighting in Yemen, as he warned that the country stands on a "precipice" and could face the world's "worst famine" for decades if violence continues unabated. In the course of this, he demanded an end to fighting, and an immediate halt to all airstrikes against populated areas.
Aviation at the airport and global aid efforts were not affected, Colonel Turki al-Malki said. The port is a key entry point for food and humanitarian aid, but the coalition says the Houthis also use it to import weapons.
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Singling out Trump, she urged him to "help reveal the truth and ensure justice be served". "He should not allow my fiance's murder to be covered up".
A previous attempt to take the city in June ran into difficulties and was halted ahead of United Nations -led peace consultations in Geneva which collapsed in September after the Houthis failed to show up.
Back in June, coalition forces, backed by armed militia loyal to Hadi, launched a full-scale offensive against the Houthi-held Hudaydah, which is now under a tight siege imposed by the invaders and through whose docks over 70 percent of Yemen's imports used to pass.
The impoverished Arab country has been locked into a civil war since the Iran-backed Shiite Houthi rebels overran much of the country militarily and seized all northern provinces, including the capital Sanaa, in 2014.
Other rights groups estimate the toll could be five times higher.
The development comes a day after the Yemeni government said it welcomed "all efforts to restore peace" following calls by key USA officials and the UN's envoy to Yemen Martin Griffiths for warring parties to come to the table "within a month".