The anti-poverty lender said Wednesday that Malpass would be leaving by June 30. His five-year term was due to expire in April 2024.

Malpass, an economist who earlier served as U.S. under secretary of the Treasury for international affairs, said in a statement that he had decided to pursue new challenges.

“With developing countries facing unprecedented crises, I’m proud that the Bank Group has responded with speed, scale, innovation, and impact,” he said. “The last four years have been some of the most meaningful of my career.”

When he got the job, Malpass had been a critic of the World Bank, arguing that it had focused too much on its own expansion and not enough on its core mission of fighting poverty.

Treasury Secretary Janet Yellen thanked Malpass for his service.

“The world has benefited from his strong support for Ukraine in the face of Russia’s illegal and unprovoked invasion, his vital work to assist the Afghan people, and his commitment to helping low-income countries” reduce their debt burden. Yellen said in a statement. President Joe Biden can now nominate Malpass’ successor.

Clemence Landers, a policy fellow at the Center for Global Development in Washington, said Malpass focused considerable energy on helping developing countries’ deal with debts.

But under his leadership, she said, the bank “ceded a lot of space’’ to its sister agency, the International Monetary Fund, and to regional development agencies.

“There are just a lot of things that the World Bank slightly missed the boat on,’’ she said, noting criticism that it had not been aggressive enough in backing projects to fight climate change or to help poor countries get access to COVID-19 vaccines.

Malpass ran into criticism last year for seeming, in comments at a conference, to doubt the science that says the burning of fossil fuels causes global warming. He later apologized and said he had misspoken, noting that the bank routinely relies on climate science.