Australia has a “perfect right” to sail naval assets through the South China Sea and a recent robust exchange in the disputed waters is symbolic of that fact, Prime Minister Malcolm Turnbull said.

Mr. Turnbull added that Australia asserted its right to freedom of navigation through all the world’s oceans, including the South China Sea, and would not be changing that approach.

He was speaking on the sidelines of the Commonwealth Heads of Government Meeting (CHOGM) now underway in London.

The Sydney Morning Herald reports Mr. Turnbull outlined Australia’s freedom of navigation rules in simple terms.

“All I can say to you is we maintain and practice the right of freedom of navigation and overflight throughout the world,” Mr Turnbull said.

“In this context, you’re talking about naval vessels on the world’s oceans including the South China Sea, as is our perfect right in accordance with international law.”

The ABC reports that the Chinese navy challenged three Australian warships on why they were in the South China Sea, citing an official who described the exchanges as “robust” but polite.

The confrontations are believed to have occurred as China was conducting its largest ever naval exercises in the hotly contested waters.

Defence sources have confirmed to the ABC that Australian warships HMAS Anzac, HMAS Toowoomba and HMAS Success were challenged by the PLA Navy as they were transiting towards Vietnam where they are now conducting a three-day goodwill visit in Ho Chi Minh City.

Earlier this month, Beijing boasted of the largest-ever military exercises by the Chinese navy in the South China Sea.

In the rare display, China brought much of its naval hardware for the world to see — 10,000 personnel, 76 fighter jets, 48 naval vessels, a nuclear powered submarine and China’s first aircraft carrier.

China claims much of the South China Sea as its own territory, even though parts of it are also claimed by six other countries.

It is keeping an especially close watch on U.S. Navy ships in the area, even sending vessels to “check out” the ships and lingering for days, according to a recent report.