SAUDI-LED FORCES ATTACK YEMENI CITY,

DUBAI, United Arab Emirates — The Saudi-led coalition backing Yemen’s exiled government launched a fierce assault Wednesday on the crucial port city of Hodeida, the biggest offensive of the years-long war in the Arab world’s poorest nation for the main entry point for food in a country already teetering on the brink of famine.

The attack on the Red Sea port aimed to drive out Iranian-aligned Shiite rebels known as Houthis, who have held Hodeida since 2015, and break the civil war’s long stalemate. But it could set off a prolonged street-by-street battle that inflicts heavy casualties.

The fear is that a protracted fight could force a shutdown of Hodeida’s port at a time when a halt in aid risks tipping millions into starvation. About 70 per cent of Yemen’s food enters via the port, as well as the bulk of humanitarian aid and fuel supplies. About two-thirds of the country’s population of 27 million relies on aid and 8.4 million are already at risk of starving.

Before dawn Wednesday, convoys of vehicles appeared to be heading toward the rebel-held city as heavy gunfire rang out. The assault, part of an operation dubbed “Golden Victory,” began with coalition airstrikes and shelling by naval ships, according to Saudi-owned satellite news channels and state media.

Bombardment was heavy, with one aid official reporting 30 strikes in 30 minutes.

“Some civilians are entrapped, others forced from their homes,” said Jolien Veldwijk, the acting country director of the aid group CARE International, which works in Hodeida. “We thought it could not get any worse, but unfortunately we were wrong.”

The initial battle plan appeared to involve a pincer movement.

About 2,000 troops who crossed the Red Sea from an Emirati naval base in the African nation of Eritrea were awaiting orders to move in from the west after Yemeni government forces seize Hodeida’s port, Yemeni security officials said.

Emirati forces with Yemeni government troops moved in from the south near Hodeida’s airport, while others sought to cut off Houthi supply lines to the east, the officials said.