Oil giant Equinor has abandoned controversial plans to drill in the Great Australian Bight in a move hailed by environmentalists as a "huge win".

The Norwegian firm was granted approval last December to begin exploratory drills in seas off South Australia.

But on Tuesday it told regulators the plan was "not commercially competitive" compared to options elsewhere.

Australia's government said the withdrawal was disappointing.

The Great Australian Bight is said to be one of the most unspoiled marine environments in the world.

Green groups have sought for decades to protect it, but Canberra has been open to extracting the possible oil riches there...

Thousands of people protested in Australia and Norway in the past year, while activist shareholders had also raised the project with the company's board…

"The Bight basin remains one of Australia's frontier basins and any proposals for new oil and gas fields in this area will be assessed fairly and independently," he said.