AUTHORITIES have delayed a controversial decision on whether to allow the dumping of dredge spoil in the Great Barrier Reef Marine Park.

The Great Barrier Reef Marine Park Authority (GBRMPA) was due to make a decision to grant permits for the developers of the Abbot Point coal port terminal to dump dredge spoil on Friday.

But the authority on Friday announced that the decision will be delayed until January 31.

"As part of this project, the Great Barrier Reef Marine Park Authority is now carefully considering the permit application from North Queensland Bulk Ports for disposal of dredge material," GBRMPA biodiversity, conservation and sustainable use manager Bruce Elliot said in a statement.

"We have extended the time for making a decision on the dredge disposal application under the Great Barrier Reef Marine Park Act until 31 January 2014."

Green groups have tentatively welcomed the news, but say the fight to stop the dumping isn't over.

WWF spokesman Richard Leck said GBRMPA needs to listen to the science, tourist operators, fishers and concerned community members and put the needs of the reef first.

"The decision by GBRMPA is a temporary reprieve for the reef," Mr Leck said.

"But the fight's not over yet. We call on GBRMPA to take the next step and rule against the reef being used as a dump."

Australian Marine Conservation Society spokeswoman Felicity Wishart said the authority was right to extend the deadline.

"The high risk posed by dumping dredge spoil in the reef's waters and uncertainty over the full extent of damage left GBRMPA little choice but to reject the issuing of a permit," she said in a statement.

"An overwhelming majority of Australians want to see dumping of dredge spoil completely banned in the World Heritage waters of the reef."