Donald Trump has threatened to impose tariffs on countries that do not ‘go along’ with his plan to annex Greenland, increasing pressure on European allies who have opposed his effort to take over the Arctic territory.

Speaking at a White House event about the tariffs he slapped on pharmaceutical imports from the EU as part of his efforts to lower drug prices in the US, Trump added: ‘I may do that for Greenland too. I may put a tariff on countries if they don’t go along with Greenland, because we need Greenland for national security.’