Australia's government has given its approval for one of the world's biggest coal mines to be built by India's Adani Mining in Queensland.
In August, a court temporarily blocked the project because of environmental concerns.
But the approval has now been granted subject to "36 of the strictest conditions in Australian history" environment minister Greg Hunt said.
Critics say the decision was "grossly irresponsible".
The approval was signed on Wednesday by Mr Hunt and follows a long running debate between those for and against the mine.
"I have the power to suspend or revoke the approval and strict penalties apply if there is a breach of the strict conditions," he said in a statement on Thursday.
First proposed in 2010, the Carmichael project is worth some A$16bn and will dig up and transport about 60 million tonnes of coal a year for export, mostly to India.
The mine will cover an area seven times the size of Sydney Harbour.
It includes a railway project and was first approved by the government last year.
But critics challenged the approval of the mine in Federal Court mainly because of concerns that two vulnerable animal species would be threatened.
The court found that Mr Hunt had failed to heed advice about threats to those species and blocked the mine from operating until fresh approval was granted.
On Thursday, Mr Hunt said the conditions he had imposed upon the Carmichael mine and its rail infrastructure project took into account "issues raised by the community and ensure that the proponent (Adani) must meet the highest environmental standards".
Some of the conditions Adani will have to meet in order for mining to proceed include the protection and improvement of 31,000 hectares of special wildlife habitat and A$1m of funding for research programmes to improve conservation of threatened species in the area over the next 10 years.
In an emailed statement, Adani said it welcomed Thursday's announcement saying it "makes clear that these concerns have been addressed, reflected in rigorous and painstaking conditions".
However, the Australian Conservation Foundation (ACF) spoke out against the approval of the mine and railway project.
"To approve a massive coal mine that would make species extinct, deplete 297 billion litres of precious groundwater and produce 128.4 million tonnes of CO2 (carbon dioxide) a year is grossly irresponsible," said ACF president Geoff Cousins.
"At a time when the world is desperately seeking cleaner energy options this huge new coal mine will make the effort to combat climate change all the more difficult," he added.
The ACF said the mine would produce more climate pollution than New Zealand's entire annual emissions.
The mine and railway project are situated in the Galilee Basin in the central Queensland region, some 300km inland.