China and Japan are two of Asia’s most powerful nations and the region’s biggest trading partners. Yet centuries of intense rivalry mean their economic embrace can never be taken for granted.

China is trying to impose economic costs on Japan for wading into the issue of Taiwan. But experts say the escalating dispute could ultimately hurt China too.

The workaholic new prime minister is riding high despite the perils of a fight with Beijing.

HONG KONG -- China will suspend imports of Japanese seafood, according to ABC News partner NHK, escalating a diplomatic dispute triggered by Japanese Prime Minister Sanae Takaichi’s recent comments suggesting Tokyo could take military action if China attacks Taiwan.

Weeks into the job, Japan’s new leader has come face-to-face with what it means to cross China’s red line on Taiwan.

China stepped up its economic war with Japan on Wednesday as a dispute between Asia’s two biggest economies intensified over a remark by Tokyo's new leader about a Japanese response to any Chinese military move against self-ruled Taiwan.

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.

If Japan’s hawkish new prime minister, Takaichi Sanae, has her way, Japan’s security evolution will quicken. The country’s military build-up is a response to increasingly aggressive neighbours in China and North Korea and to an ever more unreliable ally in America.