The US is deploying more and more freedom of navigation operations in the South China Sea and urging allies like Australia to take similar action.

"We always want to see more like-minded countries engage in this activity to build international consensus and pressure China to abide by it," a senior US official said on the threshold.

In today's AUSMIN talks, Australian Foreign Minister Marise Payne and Defense Secretary Linda Reynolds will meet US counterparts Mike Pompeo and Mark Esper in Washington to discuss expanding military cooperation in the South China Sea and anti-trust efforts.

The meeting took place in the context that the US is intensifying patrols and freedom of navigation activities in the South China Sea and persuading allies and partners to participate in preventing the ambition of demanding unreasonable Chinese sovereignty claims in the region.

Five Australian Navy warships in the middle of the month moved near Vietnam's Spratly Islands in the South China Sea, before joining forces with US and Japanese forces in the Philippine Sea for joint exercises.

In a note to the United Nations last week, Australia declared that China's territorial and maritime claims in the South China Sea have no legal basis.

High-ranking US officials said that as more countries participate in the deployment of freedom of navigation operations in the region, tensions can be reduced by "removing the US-China binary variable from the equation".

"When another country conducts a free shipping campaign, accompanies or carries out joint activities with the United States, this reinforces the message that we stand up for rules-based order and that China is the party.

US Defense Secretary Esper announced earlier this month that the US Navy warship will continue to travel through the South China Sea and help countries in the region "repel the Chinese naval aggression."

"In 2019, we launch a record number of freedom of navigation operations in the South China Sea in the program's 40-year history. We will keep this pace this year," Esper said.

Australian officials expect China to respond angrily to Canberra's new legal stance on Beijing's sovereignty claim in the South China Sea.

US Ambassador to Australia Arthur Culvahouse praised Canberra's legal statement.