How do you make the world’s coal producers cut back? Hit them where it hurts: financing.

That was the message Thursday from an executive at the Industrial and Commercial Bank of China (ICBC), China’s largest bank and the world’s largest bank by assets. ICBC is ranked 26 on Fortune’s Global 500.

As a result of sweeping stress tests to assess the impact of climate change on sectors and businesses, industries deemed to have high exposure—the coal business, chief among them—now must pay more for their debt, said Yin Hong, deputy head of the urban finance research institute at the ICBC, speaking at Fortune’s Global Sustainability Forum.

The stress tests began in 2015, said Yin, and have changed the way Chinese banks look at the businesses they fund: reducing their exposure to coal projects and increasing their exposure to renewable energy.

“The key achievement is this: we are using stress tests to quantify . . . how big is the exposure [to climate change], so that commercial banks will be able to take targeted approaches in response,” she said. That means the credit rating of the banks’ customers are influenced by the climate risk of their businesses, she said.

While Yin notes these stress tests cover a range of industries, coal is frequently targeted: China consumes over half the world’s coal, which remains by far the most polluting fuel and a major contributor to global emissions.

Tighter financing has already resulted in some coal businesses going bankrupt, said Yang Fuqiang, senior advisor to China’s Natural Resource Defense Council. But even some of the country’s largest coal businesses are feeling the impact, he said.

But if this approach resembles climate activism, bankers disagree: it’s simply risk assessment.

A group of central banks called the Network for Greening the Financial System, of which the People’s Bank of China is a member, has pushed for banks to see climate risk as a fundamental part of their mandate to ensure financial stability.

That requires a huge amount of co-operation between central banks—an approach that China is also pioneering at the domestic level, says Priscilla Lu. That’s through groups like a Green Finance forum organized by the People’s Bank of China, of which she is a member, alongside her role as managing director of sustainable investments alternatives and real assets at DWS.

In China, that collaboration “is really moving it a lot faster than anywhere else in the world,” she said.