China's defence ministry said on Thursday that Japan will have to pay a "painful price" if it steps out of line over Taiwan, responding to Japanese plans to deploy missiles on an island some 100 km (62 miles) from Taiwan's coast.

President Lai Ching-te says the spending, which must be approved by the island’s legislature, would fund purchases of arms from the United States.

Satellite imagery shared by open-source analyst Brady Africk on X showed three of China’s so-called Shui Qiang landing barges off the coast of Ningbo in Zhejiang province on November 20. A separate photo captured by European Space Agency satellites and reviewed by Newsweek shows three barges linked together.

The remarks come amid the two countries’ worst diplomatic crisis in years, after the Japanese prime minister said a Chinese attack on Taiwan could trigger a military response from Tokyo.

The Chinese military has recently posted a war simulation video on social media in which fighter jets and tanks are deployed and missiles are launched, in an apparent demonstration of its power amid an escalating diplomatic row with Japan.

The Lowy Institute pointed to China's considerable advances in air and naval technologies and long-range weapons.