Donald Trump should not worry about insulting China and if Beijing objects to him speaking to Taiwan, "screw 'em", an economic adviser to the US president-elect has said.

Stephen Moore, distinguished visiting fellow at The Heritage Foundation, a conservative think tank in Washington, said Mr Trump was right to risk China's displeasure by speaking on the phone with the president of Taiwan, which the Chinese regard as a breakaway province.

He said: "Too many namby-pamby people in the foreign policy shop are saying 'Oh my gosh we can't do this, we might insult the Chinese.' I don't care if we insult the Chinese.

"Taiwan is our ally. That is a country that we have backed because they believe in freedom. We ought to back our ally, and if China doesn't like it, screw 'em."

Mr Moore added: "We see what's happening in China the way they're sabre rattling out there in the East, it's about time we do what Reagan did, we stand up to these bullies."