The environmental group Environmental Action Germany (DUH) says it is suing to stop the controversial Nord Stream 2 natural gas pipeline from going into operation and that it is demanding a fuller accounting of the project’s potential greenhouse gas emissions, according to Clean Energy Wire.

DUH — which got the ball rolling on the diesel driving bans in place in various German cities — says it has filed a suit before the Greifswald High Administrative Court (Oberverwaltungsgericht Greifswald) to review the pipeline’s operating permit. It says it wants the Stralsund Mining Authority — the body responsible for the technical examination and approval of the pipeline — to file new findings about the leakage of the potent greenhouse gas methane related to the project. It argues that a 2018 assessment of the pipeline’s impact did not consider new findings about methane leaks associated with the extraction, transport and processing of natural gas linked to the operation of Nord Stream 2. “We are certain that Nord Stream 2 would not have been approved with the scientific findings now available,” says Constantin Zerger, head of energy and climate protection at DUH. The group is demanding that construction be suspended until proceedings are completed.

Nord Stream 2, which connects Germany with Russia via the Baltic, has already faced multiple controversies. The United States is threatening sanctions against companies involved in the pipeline, saying that it undermines European security by making the bloc more reliant on Russian energy. Washington instead wants Germany to import liquefied natural gas (LNG) — particularly from the United States. Last month, the companies involved in the pipeline called for political support to help the project move forward.