A white paper issued by Canberra on Thursday has promised an 81 percent boost in Australia’s military spending, as Beijing continues to strengthen its position in the disputed South China Sea.

The 2016 Defense White Paper calls for a total of AUD$195 billion in spending a larger force of 62,400 personnel by 2020-21—the largest in a quarter of a century.

Former Minister for Defense Kevin Andrews told the Australian Broadcasting Corporation that the country must be “prepared to sail our naval vessels, to fly our aircraft through that region and say we want unrestricted trade routes in this area.”

“We’ve been treading cautiously for months now and what’s been the response from China? The continued militarisation of […] both the East and South China Sea despite President Xi [Jinping] saying the contrary,” Andrews added.

Australia’s pledge to shore up its position in the region came just days after the Commander of the US Navy’s Pacific Fleet said it would be “valuable” if the Royal Australian Navy joined US-led “freedom of navigation” operations that have seen warships sail within 12 nautical miles of manmade islands built up by China.

The US has said it will conduct further sea and air patrols over the South China Sea to to challenge an accelerated military buildup in the contested waters, where satellite imagery has within the past week shown the deployment of advanced radar systems, surface-to-air missiles and fighter jets by China.

The Australian and US commitments come amidst a chorus of condemnation from regional neighbours such as the Philippines and Vietnam, whose foreign ministry said on Thursday that China’s military buildup “threatens stability in the region.”

Ryan Ho Kilpatrick is an award-winning journalist and scholar from Hong Kong who has reported on the city’s politics, protests, and policing for The Washington Post, Los Angeles Times, TIME, The Guardian, The Independent, and others