The world woke up to the news that Britain had decided to leave the European union. You can follow our live coverage here.

The EU's leadership has demanded Britain activate Article 50 exit talks "as soon as possible" as they attempt to end the uncertainty over the bloc, "however painful that process may be".

Donald Tusk, president of the European Council, Martin Schulz, president of the European Parliament, Mark Rutte, holder of the rotating presidency of the Council of the EU, and Jean-Claude Juncker, president of the European Commission released a statement on Friday morning.

"Any delay would unnecessarily prolong uncertainty. We have rules to deal with this in an orderly way," it said.

Tusk earlier said: "We are determined to keep our unity as 27 ... I will propose that we start a period of wider reflection on the future of our union," adding: "What doesn't kill you, makes you stronger."