A bomber attached to an aviation regiment of the PLA Navy takes off for a realistic round-the-clock flight training exercise on August 9, 2021. The training contains multiple subjects such as shock tactics against ground and sea targets, flight-refueling operations and so on. (eng.chinamil.com.cn/Photo by Yang Ling)

Amid frequent foreign military provocations from the sea, the Chinese People's Liberation Army (PLA) held more than a hundred military exercises across all major Chinese sea areas over the past three months, with Chinese military experts saying on Tuesday that the PLA has set up a strategic maritime defense perimeter and is prepared for simultaneous battles in multiple directions.

The Maritime Safety Administration on Monday announced three separate navigation restriction zones in the South China Sea, the northern Yellow Sea and the Bohai Strait for live-fire military exercises in the coming few days.

This is not the first time the PLA has organized military exercises across multiple sea areas, as it held at least 120 military exercises in the Bohai Sea, the Yellow Sea, the East China Sea, the Taiwan Straits and the South China Sea over the past three months, according to navigation notices released by the Maritime Safety Administration and releases by defense authorities on the island of Taiwan.

In the Bohai Sea and the Yellow Sea, the PLA hosted at least 48 drills since late May, making the area the most exercise-intensive among others, probably because the two seas are home to some of the PLA's maritime weapon test sites and gateways to the country's capital Beijing, observers said.

About 39 PLA exercises were observed by the armed forces on the island of Taiwan near the island in the past three months. Analysts said related drills have become routine since last year to enhance combat preparedness of the PLA and deter Taiwan secessionists and foreign forces, and the real number could be higher than the Taiwan defense authorities have reported.

Highlighted by a large-scale exercise in early August - with the exclusion zone larger than the size of the Hainan Island - the South China Sea hosted at least 26 PLA drills in the three-month period, which also saw foreign military provocations. According to the monitoring of the South China Sea Strategic Situation Probing Initiative, a Beijing-based think tank, the provocative moves include frequent US close-in reconnaissance activities, US warship trespassing into Chinese territorial waters, US and UK aircraft carrier voyages.

The PLA also held at least seven exercises in the East China Sea, which is to the north of the Taiwan island and home to the Diaoyu Islands.

While the notices by the Maritime Safety Administration did not go into detail on the training subjects featured in the exercises, official media reports after the drills shed light on some of them, with a wide variety of warships and warplanes - including almost all advanced types in service with the PLA - taking part in large and small exercises and some featuring joint operations.

Song Zhongping, a military expert and TV commentator, told the Global Times that by holding exercises in all major Chinese sea areas, the PLA is preparing to face simultaneous combat from different directions should a military conflict break out.

This also means that the PLA has established a strategic maritime defense perimeter off the coastlines, so that hostile forces must think twice before making any action, Wei Dongxu, a Beijing-based military expert, told the Global Times on Tuesday.