SANAA: The war in Yemen has killed or injured more than 5,000 children and left another 400,000 severely malnourished and fighting for their lives, the U.N. children’s agency said Tuesday. United Nations aid agencies called for the Yemeni port of Hudaida to remain open beyond Friday, the date set by an Arab-led military coalition, to permit continued delivery of lifesaving goods.

Yemen is the world’s worst humanitarian crisis, where 8.3 million people are entirely dependent on external food aid and 400,000 children suffer from severe acute malnutrition, a potentially lethal condition, they said.

In a report unveiled in Sanaa, UNICEF said nearly 2 million Yemeni children were out of school, a quarter of them since the conflict escalated when the coalition intervened in March 2015.

More than 3 million children were born into the war, it said, adding they had been “scarred by years of violence, displacement, disease, poverty, under nutrition and a lack of access to basic services.”

UNICEF said the more than 5,000 children killed or injured in the violence amounted to “an average of five children every day since March 2015.”

“An entire generation of children in Yemen is growing up knowing nothing but violence,” said Meritxell Relano, UNICEF representative in Yemen. “Malnutrition and disease are rampant as basic services collapse,” he added.

The U.N. agency said more than 11 million children – or “nearly every child in Yemen” – was now in need of humanitarian assistance.

The coalition, under international pressure, eased a three-week blockade that was imposed on Yemeni ports and airports in November in response to a ballistic missile fired by the Houthi movement toward the Saudi capital Riyadh.

Four mobile cranes arrived in the Houthi-controlled Hudaida Port, the U.N. said Monday, after the coalition agreed to let them into Yemen, where nearly three years of war have pushed it to the verge of famine.

“The port in theory is going be open to the 19th of this month. Then we don’t know if the coalition will close or [leave] it open,” Relano said.

“Obviously the feeling is that they extend this period so that the commercial goods can come in, but especially the fuel,” she said, speaking from the capital Sanaa.

Before the conflict, Hudaida Port handled around 70 percent of Yemen’s imports, including food and humanitarian supplies.

Fuel is vital to power water and sanitation stations to provide clean water and help avoid diseases, the UNICEF representative said.

“Yemen is in the grips of the world’s biggest hunger crisis,” World Food Program spokeswoman Bettina Luescher said. “This is a nightmare that is happening right now.”

Luescher, asked about prospects for the Hudaida Port lifeline to remain open, said: “Obviously since the cranes were imported and are operational, we are hopeful and optimistic that our work can continue.”

A diphtheria outbreak in Yemen is “spreading quickly,” with 678 cases and 48 associated deaths in four months, Fadela Chaib of the World Health Organization said.

Ibb and Hudaida are the worst-hit of the 19 affected governorates, she added.

“We can stop the outbreak by providing antibiotics and also vaccinating,” she said, adding that 2.5 million doses have been imported for a planned immunization campaign.

In other developments, Yemeni authorities said Tuesday that the country needs a $2 billion deposit pledged by key ally Saudi Arabia in November to stabilize a currency that hit new lows this week.

Authorities sought to boost liquidity by printing money, but the rial plunged from 250 to the dollar to 350 after the first batch of newly printed notes was rolled out last year. The rial traded for 440 to the dollar by year’s end and this week crashed to around 500.

“Government action in this regard is done on several tracks, according to the limited options available, including intensifying communication ... to expedite the completion of the Saudi depository procedures,” news agency Saba quoted government spokesman Rajeh Badi as saying Monday.

Saudi officials did not immediately respond to a request for comment about the allegedly promised funds.

President Abed Rabbou Mansour Hadi announced on Nov. 11 that Riyadh had agreed to deposit $2 billion into Yemen’s central bank to shore up the rial and secure shipments of badly needed fuel.

Hadi’s government moved the central bank in 2016 from Houthi-controlled Sanaa to the southern port city of Aden, where the government is currently based.

Both the central bank in Aden and the one in Sanaa suffer from depleted reserves, but they have played a key role in mitigating widespread economic pain by paying some public sector salaries, as soaring prices threaten to push basic commodities out of reach for many Yemenis.

The Aden authorities accuse the Houthis of plundering the bank’s foreign reserves to fund their war effort when it was based in the capital, charges the group and the Sanaa bank deny.