World Bank chief Jim Yong Kim on Monday announced that he is resigning from his post three years before his term was set to expire.

Kim wrote in an email to the bank staff that he will leave his post on February first to join a firm involved in infrastructure investment in developing countries.

The Korean-American was named the head of the bank for his first five-year term in 2012 and secured his second term in 2016, which he began in July 2017.

U.S. media said Kim's unexpected departure is likely to set off a fierce battle between the Trump administration and other countries who have complained about the influence the United States exerts over the World Bank.