Inside the world’s largest climate coalition for banks, there’s speculation that an exodus led by Wall Street could be about to spread to the European Union.

The Net-Zero Banking Alliance (NZBA), an organization dedicated to decarbonizing global finance, may be facing defections by some large EU banks with sizeable U.S. exposures, according to a person close to the matter who asked not to be identified discussing private deliberations. The risk of being accused in the U.S. of having an anti-oil bias appears to be a key concern among the banks, the person said.

EU exits from NZBA would mark a painful milestone for the group. In the U.S., where President Donald Trump’s re-election has brought with it intensified political attacks on net-zero policies, banks have had to navigate a landscape in which NZBA commitments have come with the risk of lawsuits and Republican blacklists. In the EU, meanwhile, net zero has been enshrined in law and the bloc’s banks stand out as some of the world’s most climate conscious.