European stock markets slumped to a five-week low on Friday after Donald Trump unleashed sweeping global tariffs, including a 39pc levy on Switzerland.

The Eurostoxx index dropped 1.7pc as stocks were also dragged lower by the US president’s demand that the world’s biggest drug makers must lower prices for American consumers.

Switzerland faces a double blow. It is home to some of the world’s biggest pharmaceuticals companies, and now also faces becoming an isolated island of high tariffs surrounded by European nations whose manufacturers face relatively lower taxes in exporting to the US.

The Eurostoxx index dropped 1.6pc to its lowest level since late June, while the FTSE 100 fell 0.6pc.

More than £16bn was wiped off the value of Europe’s biggest pharmaceutical companies amid fears such a move will be funded by higher charges on the rest of the world. AstraZeneca was one of the biggest fallers on the FTSE 100 on Friday morning, with shares down 3.9pc, while GlaxoSmithKline fell 1.6pc.