Global markets are facing volatility after U.S. President Donald Trump vowed to slap tariffs on eight European nations until the U.S. is allowed to buy Greenland, news that pushed the euro to a seven-week low in late Sunday trading.

Trump said he would impose an additional 10% import tariff from Feb. 1 on goods from Denmark, Norway, Sweden, France, Germany, the Netherlands, Finland and Britain, which will rise to 25% on June 1 if no ?deal is reached.

Major European Union states decried the tariff threats over Greenland as blackmail on Sunday. France proposed responding with a range of previously untested ?economic countermeasures.