NEW YORK — President Trump called on Saudi Arabia to lift its crushing blockade against its war-torn neighbor Yemen on Wednesday, hours after defying the kingdom and saying the U.S. would recognize Jerusalem as the capital of Israel.

In a statement Wednesday afternoon, Mr. Trump said he had directed members of his administration to reach out to the Saudi leadership “to request that they completely allow food, fuel, water, and medicine to reach the Yemeni people who desperately need it.”

“This must be done for humanitarian reasons immediately,” the president said.

A Saudi-led coalition of Sunni Arab forces has been battling Shiite Houthi rebels in Yemen backed by Iran for years. The war has become a proxy battle for regional superiority between Saudi Arabia and Iran, its fiercest rival. Fighting has fueled the humanitarian catastrophe in the poorest country in the Middle East, killing thousands and displacing millions.

About 7 million Yemenis — many of them children — are on the brink of starvation as the Saudi coalition has cut off access to the country. 

“We’re on the brink of famine. If we don’t receive the monies that we need in the next few months, I would say 125,000 little girls and boys will die,” an official with the World Food Programme told “60 Minutes” recently.

The State Department said Tuesday that the U.S. was watching the situation in Yemen closely and urging neighbors to allow relief to reach those in need.

“One of the things that we ask for when we speak with our partners in the region — when we speak with the Saudis — is, for example, to allow more humanitarian access in,” spokeswoman Heather Nauert told reporters. “We know that the people need that so desperately.”

Yemen was plunged deeper into crisis this week following the killing of Ali Abdullah Saleh, the longtime strongman who stepped down as president in 2012. Saleh was killed by Houthi forces in the city of Sanaa and Houthi officials said he was attempting to flee to Saudi Arabia.

Mr. Trump’s call on Saudi Arabia to allow food and supplies into Yemen came one day after he spoke to Saudi King Salman and informed the king of his decision to recognize Jerusalem as the Israeli capital. Salman stated publicly that such a move “would constitute a flagrant provocation to all Muslims, all over the world.” Both Sunni and Shia governments reacted angrily to the move on Wednesday.

Saudi Arabia has been a key partner for the Trump administration’s agenda in the Middle East. Jared Kushner, a senior White House adviser and Mr. Trump’s son-in-law, has a close relationship with the Saudi Crown Prince Mohammed Bin Salman, the 32-year-old heir who has embarked on an anti-corruption crusade and consolidated power among the country’s top ranks.

Jacqueline Alemany and Kylie Atwood contributed to this report.

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