"In order to lead the way to solutions for climate change, one of the most serious issues facing the world, we will further expand support for customers' efforts towards decarbonisation," the statement said.
The bank will also aim for carbon neutrality in its own operations by 2030, it said. The lender will provide annual updates on its progress toward the 2050 target.
Smaller rival Sumitomo Mitsui Financial Group Inc is considering halting new financing for any coal-fired power plants, without exceptions, Reuters previously reported.
"Realistically, it would be very difficult to eliminate all financing of transition projects, given Japan's energy situation," Hanzawa said.
Euro-sterling's downward trajectory stalled somewhat on Thursday after it came close to, but did not breach, the key 0.85 level in the previous session.
Versus the euro, it was down around 0.1% at 85.2 pence per euro.
US Federal Reserve Chair Jerome Powell failed to soothe investor concerns about a recent surge in borrowing costs as he spoke at a Wall Street Journal forum on Thursday, pushing the safe-haven dollar higher.
Sterling fell to a three-week low against the dollar, briefly dropping below $1.38. It was last down 0.6% at $1.3810.
Britain, where some 9 million people have been given their first dose of a vaccine, said it expected its supply of COVID-19 shots would not be interrupted.
The Philippines, which has been battling one of the worst COVID-19 outbreaks in Southeast Asia, is set to buy 20 million doses of Moderna's COVID-19 vaccine.