Australia said it was pushing for a ban Thursday of any commercial use of a pioneering technique to reduce the impacts of climate change by "fertilising" the world's oceans with iron, warning of significant risks.

Environment Minister Tony Burke said Australia had worked with Nigeria and South Korea on an amendment to the London Protocol governing waste dumping at sea which would prohibit commercial fertilisation activities.

"The amendment seeks to put mandatory regulation in place around the practice of ocean fertilisation," Burke said.

"It prohibits commercial ocean fertilisation activities, while allowing for legitimate scientific research to identify potential benefits and ways to safely manage the process."

Fertilisation works by dispersing small amounts of trace iron into the ocean to stimulate the growth of phytoplankton, microscopic plant-like organisms fundamental to the marine food chain.

Phytoplankton absorb carbon dioxide from the atmosphere via photosynthesis and essentially sequester the gas by taking the CO2 to the sea floor when they die and sink.

Burke said the unwanted byproducts of fertilisation could be "severe" and include ocean acidification, harmful algal blooms, depletion of oxygen in deep waters or other ecosystem changes and impacts to human health.

Parties to the London Protocol issued a statement of concern late last year regarding a deliberate fertilisation off west Canada by a salmon restoration corporation hoping to boost stocks of phytoplankton -- a key fish food.

Australian, French and other researchers are examining fertilisation as a possible mechanism for reducing atmospheric pollution, focusing on the nutrient-rich Southern Ocean. It is yet to be proven on a significant scale.

Burke said Australia was "leading the world" in research of the method but it was important at this early stage to keep fertilisation from becoming widespread, particularly when its potential side-effects were unknown.

"The London Protocol and convention has been concerned about this issue for some time, and in 2008 adopted a voluntary resolution prohibiting ocean fertilisation activities other than legitimate scientific research" he said.

"Adoption of Australia's proposed amendment would mean that the 42 parties to the London Protocol would take a precautionary approach while more research is undertaken."

Australia's proposed ban will come before a meeting of the parties in October in London.