Verhofstadt spoke to reporters after meeting Britain's minister in charge of leaving the EU, David Davis.

"It is impossible to find a solution that would destroy the so-called four freedoms," Verhofstadt said, according to Reuters.

"These four freedoms are key, they are a basic element of the European Union: the freedom of movement of goods, services, capital and of people. We will certainly never accept whatever development where these four freedoms at put at risk," he said.