Insurers have pulled $20 billion out of coal investments, but most are European and none of the top nine U.S. insurers has taken “meaningful action,” campaign group Unfriend Coal said on Wednesday.

Government representatives and officials at this week’s U.N. climate talks in Bonn, Germany, are working on a “rule book” for the 2015 Paris Agreement to shift the world economy from fossil fuels this century.

Fifteen insurers with more than $4 trillion in related assets under management are planning to get out of stock or bond investments in coal, Unfriend Coal, a coalition of 13 civil society groups, said in a report.

Eight of those insurers, all European, feature in a scorecard of 25 of the world’s biggest insurers tracked by the campaign group. These include Lloyd’s of London, which told Unfriend Coal it would start to exclude coal from its investment strategy in April 2018.

“Although the shift away from coal is growing, these early movers still need to do more, and most insurers have yet to do anything to prevent the risk of dangerous climate change,” Unfriend Coal said.

“The scorecard finds that no U.S. insurer has taken meaningful action.”

The scorecard includes U.S. insurers such as MetLife , Chubb and Berkshire Hathaway, as well as Australian, European and Japanese companies.

However, four European insurers, AXA, SCOR , Swiss Re and Zurich, are also making changes to their underwriting of coal, the report said.

Zurich this week said it would stop providing insurance for new thermal coal mines or for potential new clients that derive more than half their revenue from mining thermal coal. It would also not take on as insurance clients utility companies that generate more than half their energy from coal.

The company said it would “engage” with such existing clients in discussions about their medium to long-term transition plans.

AXA and SCOR already have policies to reduce their exposure to insurance or reinsurance of coal companies, while Swiss Re is preparing policy to limit its business support for thermal coal utilities and mining, Unfriend Coal said.

(Additional reporting by Brenna Hughes Neghaiwi in Zurich.)