Children have died as a result of Saudi Arabia delaying aid for Yemen by months, a children's rights group have warned.

Save the Children said shipments of aid are being delayed for months, denying hundreds of thousands of people access to urgently-needed medical aid.

In the first two months of the year, the Saudi-led coalition has prevented three of the charity's shipments of medical supplies from landing at the country's main group of Hodeida, the group said, forcing them to be rerouted and delaying their arrival by up to three months.

The shipments were carrying enough aid to help around 300,000 people, including antibiotics, surgical equipment, medicine to treat diseases like malaria and cholera, and supplies to support malnourished children.

2.1 million children are facing famine in Yemen

In the latest example, a two-tonne shipment of Save the Children's medical supplies and equipment held off the coast of Hodeida then forced to reroute by the Saudi-led coalition.

The ship, carrying supplies for 40,000 people including 14,000 children under the age of five, arrived in the smaller port of Aden 83 days later.

Supplies often have to cross active conflict zones from Aden, putting both the supplies and humanitarian staff at risk.

Grant Pritchard, interim country director for Save the Children in Yemen, said: “These delays are killing children. Our teams are dealing with outbreaks of cholera, and children suffering from diarrhoea, measles, malaria and malnutrition.

"With the right medicines these are all completely treatable — but the Saudi-led coalition is stopping them getting in. They are turning aid and commercial supplies into weapons of war.

He added: “The British public has generously donated millions of pounds to a DEC appeal for Yemen, quite understandably expecting aid would reach people in need as quickly as possible.

"To see the Saudi-led coalition blocking shipments of humanitarian supplies is simply unforgivable. The UK Government must do more to make sure aid for Yemen gets where it needs to go.”

The situation in Yemen Show all 14 1 /14 The situation in Yemen The situation in Yemen Houthi supporters trample on a US flag during a gathering mobilizing more fighters into several Yemeni battlefronts, in Sana'a, Yemen EPA The situation in Yemen People carry the coffins of men, who were killed in the recent Saudi-led airstrikes during their funeral, in the Old City of Sanaa, Yemen AP The situation in Yemen Pro-government fighters give food to Yemeni children on the road leading to the southwestern port city of Mokha. Yemeni rebels are putting up fierce resistance in a key Red Sea port city where they are encircled by pro-government force Getty Images The situation in Yemen A Yemeni stands in front of a graffiti protesting US military operations in war-affected Yemen, in Sana'a, Yemen. According to reports, US Special Forces troops allegedly disembarked from US helicopters in the Yemeni town of Yakla and attacked several houses belonging to members of the terrorist group Al-Qaeda, killing three high-ranking Al-Qaeda members and nine civilians, six women and three children. One American serviceman has been killed and three injured in the attack EPA The situation in Yemen US Special Forces troops allegedly disembarked from US helicopters in the Yemeni town of Yakla and attacked several houses belonging to members of the terrorist group Al-Qaeda, killing three high-ranking Al-Qaeda members and nine civilians, six women and three children. One American serviceman has been killed and three injured in the attack EPA The situation in Yemen A Yemeni female fighter supporting the Shiite Huthi rebels, and carrying weapons used for ceremonial purposes, takes part in an anti-Saudi rally in the capital Sanaa Getty Images The situation in Yemen Yemeni female fighters supporting the Shiite Huthi rebels, and carrying weapons used for ceremonial purposes, take part in an anti-Saudi rally in the capital Sanaa Getty Images The situation in Yemen A boy shouts slogans next to pro-Houthi fighters, who have been injured during recent fighting, during a rally held to honour those injured or maimed while fighting in Houthi ranks in Sanaa, Yemen Reuters The situation in Yemen Balls of fire and smoke rise from a Houthi-held military camp following alleged Saudi-led airstrikes, in Sana'a, Yemen EPA The situation in Yemen Yemenis search under the rubble of damaged houses following reported Saudi-led coalition air strikes on the outskirts of the Yemeni capital Sanaa Getty Images The situation in Yemen A Yemeni boy looks on as Yemenis search under the rubble of damaged houses following reported Saudi-led coalition air strikes on the outskirts of the Yemeni capital Sanaa Getty The situation in Yemen A Yemeni boy sits amidst the rubble of damaged houses following reported Saudi-led coalition air strikes on the outskirts of the Yemeni capital Sanaa AFP/Getty The situation in Yemen Marine One with US President Donald Trump flies with a decoy and support helicopters to Dover Air Force Base in Dover, Delaware, for the dignified transfer of Navy Seal Chief Petty Officer William 'Ryan' Owens who was killed in Yemen Getty Images The situation in Yemen US President Donald Trump aboard the Marine One to greet the remains of a US military commando killed during a raid on the al Qaeda militant group in southern Yemen on Sunday, at Dover Air Force Base, Delaware, US Reuters

A United Nations official visiting both sides in Yemen's civil war urged them to guarantee more access to the country's ports to let in food, fuel and medicine imports.

Yemen has been divided by nearly two years of civil war that pits the Iran-allied Houthi group against a Western-backed coalition led by Saudi Arabia.

At least 10,000 people have been killed in the fighting that has unleashed a humanitarian crisis on the impoverished country. Fighting in or near ports hampers access for aid coming from outside.

Earlier this month, the UN said Saudi-led coalition air strikes on the Yemeni port of Hodeidah, which serves territory controlled by the Houthis, had hampered humanitarian operations to import vital food and fuel supplies.

Five cranes at the port have been destroyed, forcing dozens of ships to line up offshore because they cannot be unloaded.

Nearly 3.3 million people in Yemen — including 2.1 million children — are acutely malnourished, the UN says. They include 460,000 children under age of five with the worst form of malnutrition, who risk dying of pneumonia or diarrhea.