A ship carrying food aid for Aden's beleaguered population docked in the southern Yemeni port on Tuesday, the first in months of warfare that have devastated the city, as rival factions fought in the northern suburbs.

The ship carried enough U.N. food aid to feed 180,000 people for a month, a small measure of relief for a city that has been severely damaged by the conflict between Houthi militiamen and forces loyal to deposed President Abd-Rabbu Mansour Hadi.

It had been anchored off Aden since June 26 but had to wait for a safe opportunity to berth, the World Food Programme said.

"WFP made repeated attempts to send ships to Aden, all of which until today were blocked due to severe fighting in the port area," a statement said.

The delivery was the largest in months. Two U.N. truck convoys had made it through by land last week but the airport, the scene of heavy combat, has been closed.

Residents said loyalist fighters backed by Saudi-led air strikes battled to take back Aden's northern suburbs from the Iranian-allied Houthis on Tuesday after completing their capture of the city centre.

The Houthi militia and its army allies traded artillery fire with the Saudi-backed forces in the Dar Saad and al Alam areas.

Residents and local fighters said Houthi shelling killed a family of eight in Dar Saad area.

Assisted by the air strikes, local anti-Houthi forces broke months of stalemate in Aden last week by seizing the airport and then driving the Houthis out of their last redoubt in the west of the city.

Saudi Arabia intervened in Yemen's war on March 26 in an effort to stop Houthi forces taking Aden, the last city nominally controlled by Hadi. Riyadh says it wants to restore Hadi to power in the capital Sanaa, which the Houthis seized in September.

Almost four months of air raids and civil war have killed more than 3,500 people in Yemen. Aden has suffered especially, with acute shortages of food, medicine and fuel.

Aden and the other southern provinces of Yemen have been largely inaccessible to U.N. food aid, and about 13 million people - more than half the population - are thought to be in dire need of food.

"More WFP-chartered ships are on stand-by near Aden carrying fuel and more food. WFP is working to channel food through Aden to people in need of humanitarian assistance particularly in Yemen’s southern governorates, which are largely inaccessible because of fighting," a WFP spokesman said.

Hadi's administration and the Arab military alliance are seeking to secure the city and make it a base from which to challenge Houthi control over most of the rest of Yemen.

"We're in an operation to complete the extension of our control over the city of Aden and to confront the Houthi presence at its entrances," a leader in a local militia told Reuters by phone.

Local fighters said they advanced to the area of Aqqan in Lahj province directly north of Aden, and that Arab air strikes killed around 8 Houthi fighters there and pounded the militia's positions in the nearby southern province of Dhalea.

A technical team from the United Arab Emirates had arrived to repair the battle-damaged international airport, fighters said.

Officials in the anti-Houthi forces say their offensive had been planned for weeks and benefited from training and arms deliveries from Saudi Arabia and the UAE.

The Emirates' official news agency WAM said on Tuesday that an officer from the country had been killed in the service of the Arab campaign, but did not specify where.

Reuters