Thousands of people marched in Australian cities Saturday to protest against Indian mining giant Adani's controversial plan to construct a new coal mine in central Queensland.

In the face of huge public protests and legal action from environmentalists, Adani has already cut its original plan of a massive 16.5-billion-dollar (11.9-billion-US-dollar) mega open cut mine extracting 60 million tones a year.

 It will instead go ahead with a self-funded 2-billion-dollar mine extracting 10 to 15 million tones of coal a year from the Carmichael region.

But that failed to satisfy anti-coal and climate change protesters who marched in Sydney, Melbourne, Brisbane and Cairns carrying signs with slogans including ‘There is no Planet B’ and ‘The climate is changing, why aren't we?’  Around 5,000 protesters in Melbourne and hundreds in Brisbane called on the state and federal governments to stop Adani's coal mine altogether.

So far the Australian and Queensland governments have welcomed the mine as it will provide many jobs and royalties as the coal is shipped to India.

Melbourne protest organiser Alex Fuller said people were motivated to join the rally after seeing the recent school climate change strikes.

‘People were feeling really inspired that we could create change but they were also feeling really frustrated,’ she told the Australian Associated Press news agency.

Adani Mining, which was founded by Indian billionaire Gautam Adani, said in a statement to AAP that the company recognized there are varied opinions about the Carmichael mine project and encouraged everyone to voice them safely and respectfully.