World Bank President David Malpass will step down by the end of June, nearly a year before the end of his term, according to a statement from the Bank.

It is very likely that his decision is the result of an unclear public position on climate change, with Malpass criticized for not believing in human-caused climate change.

Malpass, who was appointed to the post by former US President Donald Trump, told the World Bank’s board of directors of his resignation, saying he would pursue “new challenges”, without specifying what they would be.

“It has been a tremendous honor and privilege to serve as president of the world’s leading development institution alongside such talented and exceptional people,” Malpass said in a statement.

Over the past year, the U.S. and other major shareholders of the World Bank have demanded that the institution step up its efforts to address global challenges, including climate change, alongside its traditional mandate to fight global poverty.

Last week, US Treasury Secretary Janet Yellen called on the World Bank’s leadership to “quickly” implement reforms to free up more money to fight climate change.

The USA is the largest shareholder of the World Bank and traditionally appoints its president.

Reform of development banks, including the World Bank, has appeared on the global political agenda as rich countries grapple with questions about who pays for the catastrophic effects of hurricanes, floods and fires, the FT writes.

Smaller and less wealthy countries are trying to form a coalition within the United Nations to provide them with funds to fight the effects of global warming without increasing their national debt burden.

On Wednesday, Yellen thanked Malpass for his service to the World Bank and said the US would nominate the nominee after a “transparent and expeditious process based on meritocracy.”