(Bloomberg) -- Barclays Plc and Deutsche Bank AG are among 17 banks accused by climate law activists of “hypocrisy” over work related to a controversial North Sea oil field. 

ClientEarth, a London-based group of lawyers that brings environmental cases, wrote to the lenders asking them to justify financial or advisory services that they provide to Royal Dutch Shell Plc and Siccar Point Energy, the two firms behind the Cambo oil field project, according to a statement. 

The legal charity said that doing business with the fossil-fuel firms “makes a mockery” of the banks’ climate commitments such as signing up to the Net-Zero Banking Alliance and Collective Commitment to Climate Action.

“You cannot claim to be transitioning to net zero, while at the same time supporting clients that are spearheading a risky oil and gas project clearly at odds with net zero goals,” said Jamie Sawyer, a lawyer at ClientEarth.

The Cambo oil field project has come under fierce criticism from activists who argue that tapping the field’s estimated 170 million barrels of reserves is inconsistent with the U.K.’s policy of achieving net-zero carbon emissions by 2050. The preparatory work for the Cambo field has been postponed to next year. 

Barclays and Deutsche Bank didn’t immediately respond to requests for comment on the letters.

See also: Europe Is Key Staging Ground for Climate Lawyers Dogging Big Oil

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