The Federal Court has extended an injunction banning work at a new mine in the Tarkine region in Tasmania's north-west.

Late last year, Federal Environment Minister Tony Burke approved Shree Minerals' mine at Nelson Bay River.

Conservation group Save the Tarkine, also known as the Tarkine National Coalition, launched a legal challenge disputing the approval.

Earlier this month, Justice Shane Marshall granted a temporary injunction banning work at the site.

The injunction has been extended until the matter is heard in the Federal Court in Melbourne later in the year.

Save the Tarkine's Scott Jordan has welcomed the decision, saying it will help protect the Tasmanian devil.

"This site is in an area where there's a known healthy population of Tasmanian devils, in one of the last disease free refuges for that species," he said.

A spokesman for Shree Minerals says it would be inappropriate to comment while the matter is before the courts.

The court ordered Shree Minerals to pay costs.

The Circular Head Council has expressed frustration at the latest delay.

Mayor Daryl Quilliam says the mine has been assessed by several different groups and has been found to be sustainable.

"The three levels of government - federal, state and local government - have all looked at this proposal and we've all ticked it off, the EPA has looked at it, and we all know how stringent the EPA is."

Heritage concerns

A world heritage advisory body has criticised the Federal Government's nomination of new Tasmanian reserves.

The International Council on Monuments and Sites has made recommendations to the World Heritage Committee, which will consider listing another 170,000 hectares of Tasmanian wilderness next month.

The council says the nomination should be referred back to Government because it does not address the protection of Aboriginal heritage.

Former Liberal Senator Guy Barnett wants it withdrawn to avoid international embarrassment.

"It makes it very clear that the Federal Government hasn't done its homework, there's been no consultation whatsoever with the Tasmanian Aboriginal community and the process has been rushed," he said.

Michael Mansell from the Tasmanian Aboriginal Centre has welcomed moves for more consultation.

"Nobody told us there was a body we could go to, all we heard was through the media," he said.

Premier Lara Giddings is not fazed by the council's concerns.

"These are trees and areas that will in fact be reserved and we believe that they do qualify for World Heritage status and we're very pleased to be part of a process to have that considered."

"We hope that it will be successful and we will deal with any issues that that committee raises along that pathway."