Donald Trump has taken to Twitter to threaten North Korea, writing that the country is "looking for trouble", and that America may step in to "solve the problem".

The messages came as Kim Jong-un's regime said it was “ready for war“, and the country's state media warned of a nuclear attack against the United States should America take any military action against them.

Mr Trump is seeking to pressure China to rein in its rogue neighbour. He tweeted that he had told Xi Jinping, the country's president, who made a state visit to the US last week, that "a trade deal with the US will be far better" if Beijing solves the "North Korea problem".