The presidents of the European council, commission and parliament – Donald Tusk, Jean-Claude Juncker and Martin Schulz respectively – and Mark Rutte, the prime minister of the Netherlands which holds the EU’s rotating presidency, said any delay to Britain’s exit would “unnecessarily prolong uncertainty”.

After emergency talks in Brussels, the four said they regretted, but respected Britain’s decision.

“This is an unprecedented situation, but we are united in our response,” they said in a joint statement.

While the UK – the first sovereign country to vote to leave – would remain a member until exit negotiations were concluded, they said, Europe expected it to “give effect to this decision … as soon as possible” by triggering article 50 of the Lisbon treaty, which is effectively Britain’s formal letter of resignation.