Around 100 kilometres off the coast of Darwin, HMAS Newcastle is steaming towards a People's Liberation Army-Navy warship.

The imposing-looking Chinese frigate comes into full view, and the Australians launch a smaller boat into the Timor Sea to collect two of its crew.

In comparison to the Australian guided missile frigate commissioned in the early 1990s, the foreign visitor looks starkly more modern and technologically advanced.

The Huangshan usually inhabits the South China Sea, but now it is the first Chinese warship to be invited into Australian waters to take part in multinational war games known as "Exercise Kakadu".

HMAS Newcastle spots visiting Chinese warship the Huangshan in the Timor Sea. ( ABC News: Andrew Greene )

"You know, the more we work together, the more we'll understand each other and the more we'll respect each other," Royal Australian Navy's Commodore of Warfare Ivan Ingham said.

Commodore Ingham is spending the day onboard HMAS Newcastle to oversee the large-scale military exercises involving 27 nations, 21 warships, a submarine, and 3,000 personnel.

While the exercises involve dramatic and persistent attacks by "enemy aircraft", 50-calibre machine gun fire, and high-speed naval manoeuvres, the real excitement on Sunday was the presence of the Chinese military.

Australia's invitation to Beijing to participate in these regional exercises is significant and comes at a time of growing pushback against China's rapid militarisation of the South China Sea.

"This has shown that we can cooperate together in a really positive and meaningful way," Commodore Ingham said.

Royal Australian Navy's Commodore of Warfare Ivan Ingham is overseeing the large war exercise involving 27 nations.

In recent months, federal politicians have frequently clashed with their Chinese counterparts, particularly over allegations of Beijing's interference in Australia's political system.

While diplomatic relations have been volatile in recent times, off the Northern Territory coast the military is doing what lawmakers have struggled to achieve, with both sides coming together to learn more about each other.

The two junior Chinese officers are warmly welcomed onboard with handshakes, and they exchange pleasantries with HMAS Newcastle's crew in the mess hall below deck.

The exercises involve dramatic and persistent attacks by "enemy aircraft". ( ABC News: Andrew Greene )

For much of the day, the PLA-Navy officers politely pose and smile for photographs with their curious hosts, but they decline to answer any questions and certainly won't be drawn on the strategic tensions in the waters further north.

"They were just as excited as we are, they knew more about Darwin and everything about it than I did," Able Seaman Timothy Quirk said.

And like his colleagues, Able Seaman Quirk hopes any future encounters with the Chinese military are just as cordial.