Sustained pressure from environmental activists has prompted the Norwegian energy company Equinor to cancel plans to drill for oil in the Great Australian Bight.

It was just two months ago the government granted environmental approval to drill 372 kilometres south of the Nullarbor coastline.  But now the company cites "commercial" reasons to pull out.

"This is fantastic, it's great to see Equinor following the responsible lead of BP, Chevron, and withdrawing from proposals to drill in the bight," said Wilderness Society director Peter Owen.

"The only way to protect coastal communities and the Great Australian Bight's unique marine life is to rule out drilling permanently,"  said Greenpeace Australia Pacific's chief executive officer David Ritter, describing Equinor's decision as an "incredible win" for "coastal communities, Indigenous traditional owners, surfers, the seafood industry, tourism operators and other local businesses".

But, federal government Resources Minister Keith Pitt was disappointed.

"I know many will find Equinor's decision not to proceed with this oil exploration project in the Great Australian Bight extremely disappointing, and it is particularly hard for South Australia," claimed Mr. Pitt.