WASHINGTON — President Trump pressed Saudi Arabia on Wednesday to fully end its blockade of food, water, medicine and fuel into Yemen, a rare humanitarian rebuke to the Middle East ally that he has firmly embraced since taking office.

Saudi Arabia joined Yemen’s civil war, which pit the country’s leaders against Houthi rebels, in 2015. In November, the Saudis intensified a blockade on Yemen, stopping the entry of goods and other basic necessities, and heightening warnings of a humanitarian crisis from international aid groups.

In a brief but blunt statement, Mr. Trump called on the Saudi government to “completely allow food, fuel, water and medicine to reach the Yemeni people who desperately need it.” Mr. Trump added that lifting the blockade “must be done for humanitarian reasons immediately.”

The president’s pointed request to the Saudi monarchy came on the same day that his recognition of Jerusalem as the capital of Israel sparked anger among Saudi leaders, including King Salman, who condemned Mr. Trump’s announcement.