All-weather friends China and Pakistan on Sunday kicked off their 'Sea Guardians-2' drills off the Shanghai coast by deploying their new high-tech naval ships and fighter jets to "jointly deal with maritime security threats," as their navies stepped up cooperation in India's backyard, the Indian Ocean.

The Chinese People's Liberation Army (PLA) Navy and the Pakistan Navy, will hold the joint naval exercise in maritime and aerial spaces off Shanghai in mid-July, Captain Liu Wensheng, a spokesperson for the PLA Navy, said in a statement.

The two navies held an opening ceremony for the second edition of the Sea Guardian drills on Sunday, official media here reported.

The exercise is a "normal arrangement according to an annual schedule, and it is not aimed at a third party," Liu said.

The PLA Eastern Theatre Command Navy sent the frigate Xiangtan, the corvette Shuozhou, the comprehensive supply ship Qiandaohu, a submarine, an early warning aircraft, two fighter jets and a helicopter for the drill while the Pakistan Navy's frigate Taimur joined the exercise, state-run Global Times reported.

Taimur is the second of four powerful Type 054A/P frigates built by China. It was delivered to the Pakistan Navy in Shanghai on June 23. The first ship in the Type 054A/P-class, the Tughril, joined the Pakistan Navy Fleet in January, according to the daily's report.

Themed "jointly dealing with maritime security threats," the exercise will feature training courses including the joint strike against maritime targets, joint tactical manoeuvring, joint anti-submarine warfare and joint support for damaged vessels, Liu said.

The drill's goal is to enhance defence cooperation, conduct professional and technical exchanges, deepen traditional friendship between the two countries and the two navies, and promote the development of the all-weather strategic cooperative partnership between China and Pakistan, Liu said.

China and Pakistan face non-traditional security threats including piracy and maritime terrorists in regions like the Indian Ocean, so it has become necessary that the two countries enhance cooperation in these aspects, Wei Dongxu, a Chinese military expert, told the Global Times.

The two countries also need to jointly demonstrate their capabilities in safeguarding strategic sea lanes that transport energy and goods, Wei said. The first edition of the 'Sea Guardians' exercise was held in January 2020 in the North Arabian Sea off Karachi.

The Arabian Sea region is strategically important as major Indian ports including Kandla, Okha, Mumbai, Mormugao, New Mangalore and Kochi are located there.

The Arabian sea provides entry to the Indian Ocean where China currently has built a logistics base at Djibouti in the Horn of Africa.

Observers say Sino-Pakistan military cooperation in recent years focussed more on the Navy as China gradually stepped up its naval presence in India's backyard, the Indian Ocean.

Besides building its first military base in Djibouti in the Horn of Africa in the Indian Ocean, China has acquired Pakistan's Gwadar port in the Arabian Sea which connects with China's Xinjiang province by land in the USD 60 billion China Pakistan Economic Corridor (CPEC).

China is also developing Sri Lanka's Hambantota port after it acquired it on 99 years lease.

The modernisation of the Pakistan Navy coupled with the acquisition of the naval bases was expected to shore up the Chinese Navy's presence in the Indian Ocean and the Arabian Sea.

The newly delivered Taimur's participation in the drills indicates its high technical maturity, the success in the Pakistani sailors' training as well as the rich experience accumulated by the Tughril, Chinese analysts said.

Zhang Junshe, a senior research fellow at the Chinese People's Liberation Army (PLA) Naval Military Studies Research Institute, told the Global Times that the Type 054A, on which the Type 054A/P is based, is China's most advanced frigate.

Besides acquiring four modern naval frigates from China, Pakistan will also be getting eight Chinese submarines as part of efforts to the modernisation of the Pakistan Navy, its Chief Admiral M Amjad Khan Niazi told Chinese media earlier.

The Pakistan Navy has contracted the construction of four Type 054A/P frigates from China in 2017.