Sigmar Gabriel now knows what a frosty reception feels like. The trip to China this week by Germany’s deputy chancellor and economics minister has been a catalogue of snubs and meetings cancelled at undiplomatically short notice.

Talks with Liu He, President Xi Jinping’s top economic adviser, and with Vice Premier Ma Kai, failed to happen, as did a joint appearance with commerce minister Gao Hucheng at a meeting of the German-Chinese economic committee.

It is easy to see why Mr Gabriel got the cold shoulder. On the eve of his trip, his ministry unveiled proposals to make it easier for the government to block Chinese takeovers of German technology companies. Beijing cried foul, accusing the government of protectionism. The stage was set for a showdown.