White House spokesman Jay Carney said he did not know if Obama had spoken with Zoellick and had no information on possible successors. "There has been much speculation but I'm not going to confirm any of it," Carney said.
Zoellick said he will stay focused on being bank president until June 30 and will continue to drive policies and programs at a heightened tempo. For example, later this month the bank said he will unveil a groundbreaking study on the future structure of China's economic growth model.
Under Zoellick's leadership, the bank provided more than $247 billion to help developing countries boost growth and overcome poverty.
Zoellick said he was "pleased that when the world needed the bank to step up, our shareholders responded with expanded resources and support for key reforms that made us quicker, more effective and more open."
He said the bank was now in a strong position and ready for new challenges "so it is a natural time for me to move on and support new leadership."
Associated Press writers Ken Thomas, Anne Gearan, Martin Crutsinger and Ben Feller contributed to this report.
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