Donald Trump will demand China stop its “predatory” trade policy or face the consequences during his Asia tour this week in a row that threatens to overshadow the visit.

The White House briefed journalists that the US President will send a “clear message’ for China to stop undermining US companies by giving state support to its own firms.

A senior official said China had backed off from free market economics in recent years and warned “long term” trade relations were at risk unless there was a reversal.

The tough message risks undermining efforts to build support in the region for increased pressure on North Korea to abandon its nuclear programme.

It also opens up the US president – who has adopted an “America First” agenda – to charges of hypocrisy during a diplomatic blitz that is being closely scrutinised at home.

Mr Trump’s Asian “marathon” will see him visit no fewer than five nations in 11 days – the longest overseas trip of his presidency so far.