"I am proud to announce the project has Final Investment Decision (FID) approval which marks the official start of one of the largest single Infrastructure -- and job creating -- developments in Australia's recent history," Gautam Adani said.
A total of 11 international banks have publicly distanced themselves from the project.
The $16.5 billion Carmichael coal mine project when completed would be one of the world's largest.
The Adani group had applied for the Northern Australia Infrastructure Facility loan for building the 388-km rail line to connect the Carmichael coal mine to the sea port.
Adani will go ahead with its $15 bn mine, rail and port project.