WASHINGTON -- U.S. officials say four mobile cranes dispatched to Yemen have started unloading deliveries in Hodeidah as the war-wracked nation faces the world's worst hunger crisis.

The cranes were purchased by the UN World Food Program with funding from the U.S. Agency for International Development. They arrived in Yemen in mid-January but took several weeks to be erected.

Officials say the cranes became operational Friday. They weren't authorized to discuss the matter publicly and requested anonymity.

The port at Hodeidah handles roughly 70 per cent of Yemen's imports. The World Food Program has said the cranes can carry about 60 tons each and will significantly expand delivery of humanitarian and commercial goods.

The nearly 3-year-old Yemen war has killed more than 10,000 people, displaced 2 million and helped spawn a cholera epidemic.