TAIPEI (Taiwan News) — Japan Defense Minister Kishi Nobuo referred to Russia's annexation of Crimea in a prerecorded video for a virtual event on Friday (Oct. 22) which, according to Nikkei report, was a veiled reference to a potential Chinese attack on Taiwan.

"An invasion may begin without anyone realizing it, and a war may be fought without the use of military forces,” Kishi said at the joint symposium held between U.S. think tank CSIS and Japanese publisher Nikkei. He pointed out Moscow’s actions were illegal, but they began without deploying troops, and cyberattacks preceded any physical control of the region in 2014.

Kishi's comments come amid increasing international concern over Taiwan’s security after China sent record numbers of aircraft into the country’s air defense identification zone (ADIZ) this month and spoke of the inevitability of so-called “reunification” in official statements. Kishi’s comments seem to draw a parallel between the “gray zone” tactics employed by China and a similarly indirect strategy used by Russia seizing the Crimea.

Such hybrid warfare approaches include disinformation, economic manipulation, use of proxies, insurgencies, diplomatic pressure, and other types, per Nikkei.

Panelists at the event spoke about the need for Taiwan, Japan, and neighboring countries to stand together and deter Chinese aggression. Former U.S. Deputy Secretary of State Richard Armitage said China's pressure on Taiwan has resulted in "more and more people rallying to the side of Taiwan."

"What China has been doing is scoring its own goal," he said.

Meanwhile, John Hamre, CSIS president, said the U.S. should rejoin the Comprehensive and Progressive Agreement for Trans-Pacific Partnership (CPTPP) since "foreign policy in Asia is about trade policy.

Continuing the discussion on economic factors, Rumi Aoyama, professor at Waseda University, said China's domestic push for "common prosperity" will have "a huge impact on economic growth and social stability, which could turn China's external behavior even tougher," she warned.