MELBOURNE, Sept 30 (Reuters) - The Australian government has agreed to provide a A$220 million ($143 million) low-cost loan to privately owned Perdaman to help build a A$4.5 billion urea plant in Western Australia, the country's resources minister said on Friday.

Perdaman plans to export about half the output of the 2-million-tonne-a-year urea plant to the Asia-Pacific region, Brazil and the United States, while the rest will help cut Australia's dependence on fertiliser imports, the government said. The government loan will come from the Northern Australia Infrastructure Facility, and adds to A$255 million in two previous loans backing infrastructure to service the urea project.

"This project will be transformational for Western Australia ... and secure local farmers' access to fertiliser that is vital to ensuring food security," Minister for Resources and Northern Australia Madeleine King said in a statement announcing the loan.

Perdaman has lined up a contract to buy gas from Woodside Energy Group's Scarborough project as feedstock for the urea production.

The project is being built on the Burrup Peninsula, where an indigenous group has raised concerns about the impact emissions from the plant could have on ancient indigenous rock art.

Environment Minister Tanya Plibersek in August rejected a request from two indigenous women to block Perdaman from starting construction on the urea plant.

However, earlier this month she launched a review of the impact of industry on the ancient rock art on the Burrup Peninsula.

That review, for which there is no deadline, must weigh whether to recommend more protection for indigenous heritage on the peninsula.

The Save our Songlines group that sought to block the project said the government's money would have been better spent on moving the plant to another location "where it would not damage and desecrate Murujuga sacred sites".

A Perdaman spokesperson was not immediately available to comment.

King said Perdaman's project has been designed using the "best available technology to minimise emissions", including solar power.

($1 = 1.5399 Australian dollars) (Reporting by Sonali Paul; Editing by Christian Schmollinger and Jan Harvey)