UK votes to leave the EU and the pound falls to its lowest level in more than three decades

The United Kingdom has voted to leave the European Union. The final count gave Leave roughly 52 percent of the vote against about 48 percent for Remain, a result that most polls and betting markets had not priced in when counting began.

The pound reacted within hours. Sterling fell to its weakest level against the dollar since the mid-1980s during Asian trading, one of the largest single-day moves in the currency's modern history. Stock futures in Europe and the United States dropped, while investors moved into government bonds, gold and the Japanese yen.

Prime Minister David Cameron, who campaigned to remain, announced he would step down and leave the formal exit negotiations to a successor.

What happens next is uncertain on several fronts:

• The timing of the formal notice to leave under Article 50 of the EU treaty
• The future trading relationship between the UK and its largest export market
• Whether the Bank of England will act to support markets and the economy

The Bank of England said it stands ready to provide liquidity if needed. For markets, the vote is a reminder that political risk can move currencies faster than any economic data release, and that polling averages are not the same as certainty.