SANAA, Yemen (AP) — Battlefield commanders say fighting intensified on Friday outside the airport of the vital Yemeni city of Hodeida, pitting thousands of pro-government Yemeni fighters backed by a Saudi-led coalition of mostly Emirati forces and Iranian-backed Houthi rebels.

Ahmed al-Kawkabani, a Yemeni who leads a force known as the Tohama Brigade, told the Associated Press that his forces are currently positioned in Dawar al-Hodeida, Arabic for "Hodeida roundabout." Another Yemeni commander, Abu Zarah al-Mahrami, was quoted by Dubai-based Al-Arabiya TV network as saying that pro-government forces are "within meters" of the airport.

The assault began Wednesday to seize Hodieda's vital Red Sea port, known as the "mouth of Yemen" because it's the entry point of most of the country's imports and UN humanitarian aid.

The Saudi-led coalition accuses the Houthis of using the port to smuggle weapons and missiles from Iran. The rebels have been raining ballistic missiles down on Saudi cities from across the border. The port is also a lucrative source of revenue for the Houthis, who control most of Yemen's north since 2014.

Emirati Minister of State for Foreign Affairs Anwar Gargash said that the battle over Hodeida is essential to break a stalemate in the war, which otherwise could drag on for years.

Seizing the port "means that the Houthis will no longer be able to impose their will at the barrel of a gun," he said in a post on Twitter. "If they keep Hodeida and its revenues and its strategic location, the war will last a long time and (add to) the suffering of the Yemeni people."

Hodeida, home of nearly 700,000 people, is some 150 kilometers (90 miles) southwest of Sanaa, Yemen's capital, which is under Houthi control.

The Saudi-led coalition has imposed an air, sea, and land embargo on Yemen since March 2015, aiming to dislodge the Houthis from cities they control, paralyzing trade and access to the country. The coalition air campaign and Houthi bombardment have left more than 10,000 people dead and 2 million displaced, and devastated the country's already fragile infrastructure including the health sector, which has helped spawn a cholera epidemic.

The coalition's blockade and fighting have disrupted other supply lines, causing an economic crisis that makes food too expensive for many to afford.

International aid agencies and the United Nations have warned the assault could shut down the vital aid route for some 70 percent of Yemen's food, as well as the bulk of humanitarian aid and fuel supplies. Around two-thirds of Yemen's population of 27 million relies on aid and 8.4 million are already at risk of starving.

The U.S., which backed the Saudi-led coalition over the past years with intelligence, logistical support and air-to-air refuel of fighter jets, has not publicly opposed the assault but has urged the coalition to ensure that humanitarian aid deliveries to the port continue.

Human Rights Watch urged the United Nations Security Council on Friday to warn the warring parties that they will face sanctions if they fail to provide civilians access to desperately needed aid.

"The coalition and Houthi forces, now fighting for Hodeida, have atrocious records abiding by the laws of war," said HRW's Sarah Leah Whitson.

The rights group called on all parties of the conflict to minimize civilian harm during the fight for Hodeida.