Minister for Primary Industries, David Llewellyn, said the State's GM-free status was a key factor in the Tasmanian brand.

"Tasmania's GMO-free status is a vital factor for our primary producers, helping them realise their full potential in international and interstate markets," Mr Llewellyn said.

"The decision by some other Australian states to relax their GM bans has actually increased the value of Tasmania's GMO-free status.

"It provides us with opportunities for even better Tasmanian access to prime markets."

The commercial release of genetically modified food crops is now banned until November 2014.

The ban prohibits the unauthorised importation of genetically modified organisms, but does not apply to the importation of non-viable materials, such as processed animal feeds and food.

Anti-GM lobby group, Gene Ethics, has welcomed the move, claiming it was supported by all political parties and the community.

Gene Ethics director, Bob Phelps, says the move will be "an economic winner for the state".

"The Tasmanian inquiry into GM reached all-party agreement that the ban should stay," he said.

"This consensus was based on clear evidence that commercial GM releases pose unacceptable hazards and costs.

"Tasmania's decision will protect the integrity of its clean, green brand and increased sales of top quality GM-free foods in Australia and around the world, at premium prices.

"In contrast, NSW, Victoria and WA have sacrificed the independence of their farmers to the GM giants and the reputation of their food products."