Japan’s government plans to name a private equity executive as the first ever chief investment officer of the nation’s $1.1 trillion public pension fund this week, immediately making him one of the most important investors in the world, according to several people familiar with the matter.

The government will name Hiromichi Mizuno, currently a partner with London-based private equity firm Coller Capital, to the new role at the Government Pension Investment Fund, the people said.