By Elizabeth Howcroft PARIS (Reuters) -European stocks opened slightly higher on Wednesday, showing little reaction to U.S. President Donald Trump's announcement that he would impose a 50% tariff on imported copper and soon introduce levies of up to 200% for pharmaceuticals.

Copper surged to a record high after Donald Trump said he planned to impose 50pc tariffs on imports of the vital metal. US contracts of copper, an essential part of electrical cables and devices, climbed as much as 17pc to an all-time high after the President’s comments during a White House cabinet meeting.

Trump also said he would soon announce tariffs “at a very, very high rate, like 200%,” on pharmaceutical imports.