LONDON (AP) — Britain voted to leave the European Union after a bitterly divisive referendum campaign, toppling the prime minister Friday, sending global markets plunging and shattering the stability of a project in continental unity designed half a century ago to prevent World War III.

The decision launches a yearslong process to renegotiate trade, business and political links between the United Kingdom and what would become a 27-nation bloc, an unprecedented divorce that could take decades to complete.