US President Joe Biden and Chinese President Xi Jinping have spoken on the phone for the first time since their crisis meeting in California in November, the White House said on Tuesday. After a year of complete radio silence, the two presidents met in person last November near San Francisco in order to stabilize strained relations. They promised to follow up with regular phone calls – an agreement that has finally been honoured. A high-ranking representative of the US government said that further dialogue at Cabinet level was to be expected after the presidential telephone call. US Treasury S…