Report critical test of Great Barrier Reef's health

Climate change remains the single biggest threat to the Great Barrier Reef. (Dean Lewins/AAP PHOTOS)

The Great Barrier Reef's world heritage status is under pressure as the United Nations committee orders a full report on efforts to protect the marine wonder.

Federal Environment Minister Murray Watt is in Paris for the World Heritage Committee's 47th session where the committee adopted a draft decision from UNESCO released in May.