The Commonwealth Bank's first climate policy statement has been blasted by a leading environmental investor activist group for being scant on detail and lagging the commitments of its banking peers in Australia.

The bank released its climate statement on Monday, a day when its corporate governance was also in the spotlight with the announcement chief executive Ian Narev will exit amid allegations the country's biggest bank breached anti-money laundering rules.

The CBA pledged to finance $15 billion by 2025 for what it dubbed low-carbon projects such as renewable energy and energy-efficient buildings. That would form part of the bank's support for a net-zero emissions economy by 2050 to limit dangerous climate change.

"Climate change poses a significant risk to our environment, our economy and our society," the bank said.