A UN-chartered ship loaded with 23,000 tonnes of Ukrainian wheat destined for millions of hungry people in Ethiopia docked in neighbouring Djibouti on Tuesday.

The bulk carrier MV Brave Commander arrived in the Horn of Africa port city two weeks after leaving a Black Sea port in Ukraine, the UN's World Food Programme said.

"The food on the Brave Commander will feed 1.5 million people for one month in Ethiopia," said WFP's regional director for East Africa, Mike Dunford.

"So this makes a very big impact for those people who currently have nothing. And now WFP will be able to provide them with their basic needs."

Ethiopia, with Kenya and Somalia, is in the grip of a devastating drought that has left 22 million people at risk of starvation across the Horn of Africa, the WFP said this month.

The WFP said the wheat from the Brave Commander was being taken to its operations in Ethiopia.

It was not immediately clear whether the delivery would be affected by a resumption of fighting between government forces and Tigrayan rebels in the north of the country.

Ukraine, one of the world's largest grain exporters, was forced to halt almost all deliveries after Russia's invasion in February, raising fears of a global food crisis.

But exports of grain, food and fertilisers from three Black Sea ports resumed at the start of this month under a deal between Kyiv and Moscow, brokered by the UN and Turkey in July.

The agreement lifted a Russian blockade of Ukraine's ports and set terms for millions of tonnes of wheat and other grain to start flowing from silos and ports.

US Secretary of State Antony Blinken, welcoming the ship's arrival and Djibouti's role, said the United States will be "closely monitoring Russia's adherence" to the deal.

"We call on Russia to immediately cease its war on Ukraine, which would do much to address the recent spike in global food insecurity," Mr Blinken said.

According to figures late last week from the Joint Co-ordination Centre that manages the sea corridor, more than 720,000 tonnes of grain have already left Ukraine.

The WFP said the Djibouti port is one of the main corridors it uses for its operations in East and Central Africa, handling 960,000 tonnes of food commodities in 2021.

The Horn of Africa is experiencing its worst drought in 40 years and the UN's World Meteorological Organisation warned last week that the situation is likely to get even worse with a fifth consecutive failed rainy season.

"There is still no end in sight to this drought crisis, so we must get the resources needed to save lives and stop people plunging into catastrophic levels of hunger and starvation," WFP executive director David Beasley said earlier this month.

The WFP says famine is a "serious risk," particularly in Somalia where nearly half the population of 15 million is seriously hungry.

The WFP says food insecurity and malnutrition are a major concern in Ethiopia, with an estimated 20.4 million people in need of food support, including those forced from their homes by the conflict in the north as well as the severe drought in the south and south-east.

Northern Ethiopia has been racked by war since November 2020 when Prime Minister Abiy Ahmed sent troops into Tigray to topple the Tigray People's Liberation Front after what he said were attacks by the rebels on federal army camps.