At least 150 people have been killed in 24 hours of clashes in Yemen's Hodeida, medics and military sources said yesterday, as international pressure mounted for a ceasefire in the vital port city.

Government loyalists supported by a Saudi-led coalition are fighting to oust the Iran-backed Huthi rebels from the Red Sea city, whose docks are a lifeline to 14 million Yemenis at risk of starvation.

"If the port at Hodeida is destroyed, that could create an absolutely catastrophic situation," UN Secretary General Antonio Guterres warned.

"The fighting must stop, a political debate must begin, and we must prepare a massive humanitarian response to avoid the worst next year," he said.

A military source in the pro-government coalition said the insurgents had pushed back a large-scale assault aimed at moving towards the port, under rebel control since 2014.

In a statement sent via the Telegram messaging app, the Huthis said they had "lured" loyalists up the western coastline of Hodeida, where the rebels then launched an attack on the troops.

Government forces, led on the ground by Emirati-backed troops, have made their way into Hodeida after 11 days of clashes, reaching residential neighbourhoods in the east on Sunday and sparking fears of street fights that would further endanger civilians trapped in the city.

Residents and government military sources have reported rebel snipers stationed on rooftops in civilian streets in eastern Hodeida, a few kilometres (miles) from the port on the western edge of the city.