Brisbane: US Defence Secretary Lloyd Austin has said that Washington stands with the nations resisting China's "bullying behaviour," as he began bilateral talks in Australia to oppose Beijing's sweeping claims in the Asia-Pacific.

For the negotiations, which will also centre on an agreement to give Australia a fleet of submarines powered by US nuclear technology, Austin and US Secretary of State Antony Blinken landed in Brisbane, Australia, late on Friday.

During his opening remarks in Australia on Indo-Pacific, Austin said, "We've seen troubling PRC coercion from the East China Sea to the South China Sea, to right here in the Southwest Pacific."

"We'll continue to support our allies and partners as they defend themselves from bullying behaviour," the Pentagon chief added.

The relations between China and Washington have deteriorated lately due to numerous issues, including trade, Taiwan's legal status, China's sweeping claims in the South China Sea, and an ongoing US campaign against expanding Chinese dominance in the Asia-Pacific region, Al Jazeera reported.

"Today, our cooperation is key. It's key to our shared vision of a free and open Indo-Pacific in a world of rules and rights. We seek a region where all countries are secure and prosperous, where states follow international law and international norms, and where disputes are resolved peacefully without coercion," Lloyd Austin said.

Senior US officials have visited China recently, including Blinken and Treasury Secretary Janet Yellen, in an effort to improve relations between the two nations and prevent a conflict.

The diplomatic relations between China and US have been downgraded since the Chinese spy balloon incident.