Three of the largest insurers in Europe and a Japanese insurer have reportedly quit the Net-Zero Insurance Alliance (NZIA), amid growing U.S. political pressure and legal fears, according to news reports.

In a Thursday statement, Allianz, Axa, the group’s former chair, Scor, and Japanese insurer Sompo Holdings said that they were leaving the NZIA, according to a Financial Times report.

The latest departures bring the total number of large insurers to leave the initiative to at least eight.

U.S. Republican politicians have been targeting climate action groups they perceive to be unfairly “boycotting” the oil and gas industry.

France’s Axa arm said it would continue its own sustainability journey on Thursday, while Allianz said it was fully committed to a parallel organization for asset owners. The other two insurers that quit the NZIA also pledged they were still pursuing their own climate goals.

In a Wednesday statement, the NZIA acknowledged that some members of the alliance, particularly those with significant U.S. business and exposure, have made the individual and unilateral decision to either remain or withdraw from the NZIA.

“Regardless of the situation, UNEP [UN environment programme] reaffirms its conviction ever since it initiated, convened, and launched the NZIA—that in order to successfully tackle the climate emergency, there is a fundamental and urgent need for collaboration, not just individual action.”