Sydney (AFP) - Australia said Thursday it will ban the dumping of dredging waste on most of the Great Barrier Reef as environmentalists called for the government to go further and commit to a total halt.

Conservationists say that dumping waste in reef waters will hasten its demise, with dredging smothering corals and seagrasses and exposing them to poisons and elevated levels of nutrients.

The plan, announced by Environment Minister Greg Hunt at the once-a-decade World Parks Congress in Sydney, came as the Australian government said it would set aside Aus$700,000 (US$610,000) to fund a clean-up of marine debris in the reef area.

A further Aus$6 million in funding was also unveiled by Foreign Minister Julie Bishop on Thursday to support the sustainable use of Coral Triangle waters by South East Asian countries Indonesia, Malaysia, Papua New Guinea, the Philippines, the Solomon Islands and East Timor.

Hunt said his government would enshrine in law the ban on the dumping of dredge spoil -- waste material left over from port expansion, digging out harbours, rivers and other waterways -- in the Great Barrier Reef Marine Park.

"We will use the Great Barrier Reef Marine Park Authority Act... to put in place this ban in legislative form," Hunt told reporters.

The minister had earlier told Congress delegates that enforcing the ban on dredge disposal through laws would ensure "it will not be something that we face again, and that is our pledge to this conference".

- 'Important step' -

The marine park almost totally overlaps with an expanse designated as a World Heritage Area, but the marine park does not include most islands and ports, as well as lakes and other waterways in the slightly larger heritage area.

The World Wildlife Fund (WWF) welcomed Hunt's plan, describing it as an "important step towards a complete halt to this damaging practice".

But the environmental organisation urged the minister to go a step further and prohibit the dumping of dredge soil throughout the World Heritage Area, and not just within the marine park.

"More than 80 percent of dumping since 2010 has occurred outside the marine park but within the World Heritage Area where it can easily drift onto coral and seagrass," WWF Australia's chief executive Dermot O'Gorman said.

"As we get closer to (the World Heritage Committee meeting in June), we urge the government to build on this and announce a full ban on dumping in the entire Great Barrier Reef World Heritage Area."

A World Heritage Outlook report released Thursday by the International Union for Conservation of Nature (IUCN), organisers of the Congress, said the reef's fragile ecosystem and marine biodiversity was at risk and the site was assessed as being of "significant concern".

Australia has come under scrutiny from the United Nations Educational, Scientific and Cultural Organisation over the reef's health.

UNESCO threatened to put the reef on its World Heritage in danger list, but has delayed taking action until February 1, 2015 to allow Australia to submit a report on how it will protect the bio-diverse site.

Canberra has since released a draft 2050 plan to save the reef, while the Queensland government says it will now consider only onshore plans to dump dredge waste from the port development at Abbot Point, on the Barrier Reef coast.

A marine dumping proposal was previously approved for the development, which is part of a major India-backed mine expansion.