It is in China's own best interest to seek peaceful reunification, but the possibility of using force still exists for "separatist acts" in Taiwan, said Zhou Bo, a senior fellow at the Center for International Security and Strategy, Tsinghua University.

The researcher gave the warning in response to US House Speaker Nancy Pelosi's proposed visit to Taiwan.

Zhou said that China is still patient with the Taiwan question given its defense budget has remained almost the same, well below two percent, over decades. "We only take non-peaceful means, the use of force, as a last resort," said Zhou.

Zhou also explained that China's Anti-Secession Law has laid out three very clear conditions under which China would be justified in using "non-peaceful means and other necessary measures to protect China's sovereignty and territorial integrity: Taiwan independence forces cause Taiwan's secession from China; major incidents entailing Taiwan's secession from China occur; possibilities for peaceful reunification are completely exhausted."

"To avoid this kind of miserable situation, we have to encourage more interactions across the Straits. We have to let the Chinese mainland have confidence that there is still a possibility for peaceful reunification. That is the best way to prevent a war across the Straits," Zhou said.