The U.K. voted to quit the European Union after more than four decades, in a stunning rejection of the continent's postwar political and economic order, prompting Prime Minister David Cameron to resign and sending shock waves around global markets.

The pound plunged to the lowest since 1985, European stocks followed Asian equities in tumbling, and U.S. Treasuries surged in one of the most dramatic 24 hours in modern British history. The final tally, announced just after 7 a.m. London time, showed voters had backed "Leave" by 52 percent to 48 percent. The government's pro-EU campaign was defeated by more than 1 million ballots.

"The British people have made a very clear decision to take a different path, and as such I think the country requires fresh leadership," Cameron said in an emotional statement to reporters outside his Downing Street residence in London on Friday. He said he'll stay on for the next three months with a new Conservative leader to be installed by October.