European Union President Donald Tusk says that voting to leave the bloc would be a geopolitical setback for Britain, and it would take at least seven years to negotiate a new Britain-EU relationship.

In an interview with German daily Bild published Monday, Tusk said a vote to leave in the June 23 referendum "would be a setback not just economically but above all geopolitically for Britain."

He was quoted as saying that no one can foresee the long-term consequences but he fears "Brexit could be the beginning of the destruction not just of the EU but of the entire political civilization of the West."

Tusk said cutting treaty links between Britain and the EU would take around two years and negotiating a new relationship would take at least another five.