The US and China have broached the once taboo subject of how to work together in the event of a collapse of the North Korean regime, a sign that Beijing is taking seriously the threat of war on the Korean peninsula.

Previously Beijing had refused to discuss contingency plans for a North Korea conflict, for fear of worsening an already tense relationship with Pyongyang. Such a move might also provoke members of China’s nationalist-minded elite, who can regard such talks as conspiring against a communist ally.

However, last month the first such discussions were held in Washington between the Chinese and US militaries. Major General Shao Yuanming, deputy chief of China’s joint staff department, met Lieutenant General Richard Clarke of the US joint chiefs of staff for the first meeting of a new “China-US joint staff dialogue mechanism”, according to China’s ministry of defence.