More than 5,000 military personnel from Indonesia, the US, Australia, Japan and Singapore are participating in this year's exercise, making it the largest since the drill was established in 2007.

Canada, France, India, Malaysia, South Korea, New Zealand, Papua New Guinea, Timor Leste and the United Kingdom, have joined the exercise as observer nations, according to a statement from the Indonesian Military (TNI).

This year's expanded exercise, dubbed “Super Garuda Shield”, will last until Aug. 14 and involves the Army, Navy, Air Force and Marines. Past Garuda Shield exercises were mainly held between Indonesia and the US military on a bilateral basis.

TNI commander Gen. Andika Perkasa, along with Gen. Charles A. Flynn, the commander of the US Army Pacific (USARPAC), opened the exercise with a ceremony at the Baturaja military training ground in South Sumatra on Wednesday.

“Super Garuda Shield 2022 is a joint exercise on quite a large scale between Indonesia and partner countries in the Indo-Pacific,” Andika said on Wednesday, as reported by Antara news agency.

Read also: Indonesia, US to hold military exercise amid heightened Indo-Pacific tensions

Meanwhile, Flynn said in a press release that this year’s event was an important expression of teamwork, interoperability and unity of the participating nations as a group that “seek to have a free and open Indo-Pacific and maintain a rules-based order”.

In addition to Baturaja, other locations of the joint exercise include Sultan Mahmud Badaruddin Airport in Palembang, also in South Sumatra, the Dabo Singkep marine training center in Riau Islands and the Amborawang military training ground in East Kalimantan.

Experts said that it was an opportunity for Indonesia to show the participating countries that the host country viewed maritime security as more critical than ever and that Indonesia is working with all sides for the common interest and welfare while maintaining a “free and active” foreign policy.

Analyst Dedi Dinarto also said that the choice of Amborawang in East Kalimantan as another site for exercise was significant as it is near to the location of the new Indonesian capital of Nusantara.

“This is a platform for the Indonesian military to show its readiness in terms of protecting and defending the new capital from any potential threats,” Dedi said.

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Despite being primarily a bilateral affair between Indonesia and the US, it was reported in December last year that China had sent a diplomatic note to Indonesia protesting Garuda Shield, saying that it would destabilize the region.

The US and its allies have expressed growing concern about China's increasing assertiveness in the Pacific, but Washington said last week that the drills were not aimed at any country even though they would be significantly larger than previous exercises, AFP reported.

Dedi noted that China had not made any official remarks on the 2022 Super Garuda Shield, partly because it appeared to be preoccupied with US House Speaker Nancy Pelosi’s visit to Taiwan. Pelosi arrived in Taiwan on Tuesday evening despite warnings and protests from China, which considers Taiwan as its territory.

Late last year, the US, UK and Australia formed a new security partnership dubbed AUKUS to respond to China's growing military assertiveness in the Indo-Pacific region.

“Regardless of what China might think about the exercise, Indonesia’s free and active foreign policy allows it to interact with any foreign countries,” Dedi said.

Centre for Strategic and International Studies international relations researcher Fitriani earlier said: “Let’s hope that China will not be too concerned [over the military exercise], especially with Pelosi’s plan to visit Taiwan”.

Australian Army chief Lt. Gen. Simon Stuart, who was in Baturaja for Wednesday’s opening ceremony, said in a press release that Australia would focus on the exercises as "a vehicle to continue to improve military responsiveness and build cooperative ties with Indonesia".

"By bringing our forces together, we will continue to build enduring confidence and trust," he added.

Some 90 Australian troops were to train with the Indonesian military, with a focus on "combined arms interoperability".

– Yvette Tanamal contributed to this report.