US congressmen have accused the Natural Resources Defense Council, a prominent New York-based non-government organisation, of being an agent of Chinese influence, in an escalation of Republican pressure against environmental lobbyists.

The NRDC was a vocal supporter of the Obama administration’s efforts to secure US participation in the Paris climate change agreement of 2015, which sought voluntary commitments from nations to limit their emissions of carbon and other greenhouse gases that cause global warming.

Since then, the group has been an aggressive opponent of the Trump administration’s decision to pull out of that accord and dismantle decades of US air and water quality regulations. The accusation comes as tensions between the US and China heat up, fuelled by trade friction and a broader strategic and geopolitical rivalry.