Brussels has waded into the furore over plans for a £3 billion offshore wind farm near North Devon, saying enough may not have been done to protect wildlife.
The European Commission is to investigate a complaint that the Atlantic Array development of 240 turbines could endanger the habitat of harbour porpoises which make their home in the Outer Bristol Channel.
In a letter to campaign group Save our Marine Mammals (SoMM), the acting head of the environment directorate said a notice had been sent to the UK Government.
It raises concerns about the failure to protect the species at a number of sites, including that of the array, and asks for a formal response.
Joanne Bell, of SoMM, said it was a step in the right direction: "The range of the harbour porpoise is right across the Bristol Channel," she said.
"They live there, feed there and raise their babies there.
"You can't just put an Atlantic Array in the middle and not expect it to have an impact."