China views its rare earths as a national security issue, not a trade one, and that’s why Beijing is unlikely to loosen controls any time soon, experts say.

The scramble in recent weeks to secure export licences for rare earths shows China has devised a better, more precisely targeted weapon for trade war.

Donald Trump has said he will visit China after speaking to its leader Xi Jinping over the phone. The US president said he had reciprocated with an invite to the White House during the "very good talk" - though such a trip has not been confirmed by either side.