The European Union has put its 'trade bazooka' on the table in the wake of President Donald Trump's continued threats to size Greenland.

Gold and silver prices climbed fresh peaks on Monday, as investors flocked to safe-haven assets on intensifying tensions, after U.S. President Donald Trump threatened to impose extra tariffs on European countries over the control of Greenland.

Trump's interest in Greenland isn't random – the Arctic island holds military bases and rare earth minerals as ice melts open strategic opportunities.

Denmark, Norway, Sweden, France, Germany, the United Kingdom, the Netherlands and Finland are casting a united front after Trump threatens tariffs.

The Danes have tried everything to pacify an unpredictable president. Now they may be reaching their red line.

Some protesters expressed fears that if they spoke out about Trump, his administration could bar them from visiting the United States.

An emergency meeting of EU ambassadors will take place in Brussels on Sunday in response to Trump’s threat, which he made after an estimate quarter of the population of Greenland’s capital Nuuk joined protests against any potential annexation.