An Australian court Wednesday overturned a government approval for building Australia’s largest coal mine by India’s Adani Group. While environmentalists hailed the verdict against the controversial Carmichael coal mine project -- estimated to cost 16.5 billion Australian dollars ($12.2 billion) -- in Queensland, the Indian conglomerate said that the ruling was the result of a “technical legal error.”

The Federal Court of Australia found that the country’s Environment Minister Greg Hunt failed to properly consider advice about two vulnerable species -- the yakka skink and the ornamental snake -- that are found only in Queensland, the Sydney Morning Herald reported. The legal challenge was launched by the Mackay Conservation Group in January, alleging that greenhouse gas emissions from the mine threatened species and Adani's environmental track record had not been taken into account by the government at the time of granting approval for the coal mine in July 2014.

“The Minister conceded that he had made an error and Adani did as well that the proper process hadn't been followed in approving the Carmichael mine,” Ellen Roberts, a coordinator for the conservation group, told Sydney Morning Herald. "He is required to take advice from his department on threatened species into account and he didn't do that.”

The Adani Group reportedly said that "certain documents" were not presented by the Australian environment department when it finalized the mine and rail project, which is expected to produce up to 60 million tons of coal for export every year, mostly to India.

In an emailed statement to the Wall Street Journal, the company said it hoped the approval would be granted. “Adani is confident the conditions imposed on the existing approval are robust and appropriate once the technicality is addressed," it said.

According to the supporters of the project, it will help the Indian government bring electricity to millions of people currently living without power supply. Australian Prime Minister Tony Abbott also recently praised the project as a “miracle” that “could improve the lives of 100 million Indians.”

Meanwhile, the environment department said that a “technical administrative matter” messed up the way advice was provided to Hunt before he approved the project.

“Without pre-empting a final decision about the project, the department expects that it will take six to eight weeks to prepare its advice and the supporting documentation, and for the minister to reconsider his final decision,” the department said on its website.