Global capital markets reeled on Friday after Britain voted to leave the European Union, with $2 trillion in value wiped from equity bourses worldwide, while money poured into safe-haven gold and government bonds. Sterling suffered a record plunge.

The Bank of England, the European Central Bank and the People's Bank of China all said they were ready to provide liquidity if needed to ensure global market stability.

The blow to investor confidence and the uncertainty the vote has sparked could keep the US Federal Reserve from raising interest rates as planned this year, and even spark a new round of emergency policy easing from major central banks.

Stocks on Wall Street opened more than 2 percent lower but cut losses after about an hour of trading. In Europe, stocks tumbled with London's FTSE dropping 2.4 percent.

Britain's big banks took a $100 billion battering, with Lloyds, Barclays and Royal Bank of Scotland BS plunging as much as 30 percent.

The British pound dived by 18 US cents at one point, easily the biggest fall in living memory, to its lowest since 1985. The euro, in turn, slid 3 percent to $1.1050 as investors feared for its very future.

The British pound dropped by 18 US cents at one point, easily the biggest fall in living memory, to its lowest since 1985. The euro, in turn, slid 3 percent to $1.1050 as investors feared for its very future.bre

The traditional safe-harbor assets of top-rated government debt, the Japanese yen and gold all jumped. Spot gold rose more than 5 percent and the yield on the benchmark 10-year US Treasury note fell to lows last seen in 2012 at 1.5445 percent.

Worries that other EU states could hold their own referendums were compounded by the fact that markets had rallied on Thursday, seemingly convinced the UK would vote to stay in.

Having campaigned to keep the country in the EU, British Prime Minister David Cameron announced he would step down.

Results showed a 51.9 percent split for leaving, setting the UK on an uncertain path and dealing the largest setback to European efforts to forge greater unity since World War II.

More angst came as Scotland's first minister said the option of another vote for her country to split from the UK, which was rejected by Scottish voters two years ago, was now firmly on the table.

Emerging market currencies across Asia and eastern Europe and South Africa's rand all buckled on fears that investors could pull out. Financial markets have been gripped for months by worries about what a British exit from the EU would mean for Europe's stability.

"Obviously, there will be a large spill-over effects across all global economies ... Not only will the UK go into recession, Europe will follow suit," predicted Matt Sherwood, head of investment strategy at fund manager Perpetual in Sydney.