LONDON—The United Kingdom filed for divorce from the European Union on Wednesday, overturning four decades of integration with its neighbors, demolishing the notion that EU expansion is inevitable and shaking the foundations of a bloc that is facing challenges to its identity and its place in the world.
Britain’s top envoy to the EU, Tim Barrow, hand-delivered a letter to European Council President Donald Tusk formally triggering a two-year countdown to the final split.
“Today the government acts on the democratic will of the British people,” Prime Minister Theresa May told lawmakers in the House of Commons, adding, “This is an historic moment from which there can be no turning back.”
Tusk tweeted that “after nine months the U.K. has delivered,” followed by a photo of Barrow handing him the letter in front of British and EU flags in Brussels.
There is “no reason to pretend this is a happy day,” Tusk told reporters later, emphasizing that the priority now is to minimize costs for EU citizens and member states.
To Britain, he said: “We already miss you.”
