“Political attacks” are interfering with insurers’ efforts to price climate risks, the Glasgow Financial Alliance for Net Zero said on Friday, after a wave of insurers quit an industry climate group following pressure in the United States.

“These political attacks are now interfering with insurers’ independent efforts to price climate risk, which will harm policyholders, main street investors and local economies,” a spokesperson for GFANZ, a United Nations-backed coalition of financial institutions launched by ex-Bank of England Governor Mark Carney, said in a statement.

Allianz, AXA and SCOR, three of Europe’s biggest insurance firms, on Thursday became the latest insurers to quit the Net-Zero Insurance Alliance following accusations from some U.S. Republican Attorneys General that they are violating antitrust laws.

Japan’s SOMPO Holdings, a major Asian insurer, was no longer on the list of members on NZIA’s website on Friday. It would be the first insurer outside of Europe to quit the alliance. A SOMPO spokesperson did not immediately respond to a request for comment.

The exodus of some of the world’s biggest insurers has raised questions about the viability of the NZIA, which was established in 2021. Lloyd’s of London CEO John Neal told Reuters this week the alliance needed to make its membership rules less prescriptive, or it risked falling apart.

NZIA members held several calls this week on the alliance’s options, sources say.

Some Republican politicians have mounted a campaign against financial institutions collaborating to try and rein in carbon emissions, part of a broader push back against businesses using environmental, social and governance-related factors in their decision-making.

Vanguard, one of the world’s biggest asset managers, in December left another alliance for fund managers, citing a need for independence, although other GFANZ groups have largely withstood the pressure.

Related story: More Insurers Leave Climate Alliance

Legal experts say it would be hard to make a legal case against insurers for breaching antitrust laws, and the NZIA has sought legal advice when setting requirements for members. But insurers are worried about a showdown with Republicans mounting a high-profile campaign.

Consumers’ Research, an activist group that has been highly critical of ESG policies, said on Thursday it would use a mobile billboard outside of NZIA members’ U.S. offices to pressure them to quit.

Most of those to have left the NZIA have sizeable U.S. businesses, but so do some of those still in the group. Some of the insurers to have quit also remain part of other GFANZ alliances.

“Despite these political headwinds, we will continue to support insurers’ efforts to manage climate risk and develop transition plans,” the GFANZ spokesperson said in the statement.

GFANZ, co-Chaired by Carney, was launched in 2021 ahead of the U.N. climate summit, COP26, in Glasgow.

(Reporting by Tommy Reggiori Wilkes; editing by Simon Jessop and Conor Humphries)