US shares closed at record levels, helped by Japan's surprise move to step up its stimulus measures.

The Dow Jones Industrial Average rose 1% to close at a record 17,390.52. The S&P 500 also closed at an all-time high to reach 2,018.05, up 1%.

Markets in Europe and Asia had recorded strong gains earlier.

The Bank of Japan surprised markets when it announced that it would increase its asset buying plan to 80 trillion yen ($726bn; £454bn) a year.

That was up from the previous rate of 60-70 trillion yen.

"The Japanese central bank has taken the QE baton from the Fed and equity traders couldn't be happier," said David Madden, market analyst at IG.

Among individual shares, travel firm Expediajumped more than 5% after it reported strong results for the third quarter.

Groupon soared 22% after the discount coupon firm reported third-quarter profits and revenue that beat expectations.

Starbucks shares fell 2.3% after the coffee chain's sales in the Americas region fell short of forecasts.

Starbucks reported a 5% rise in underlying sales at its stores in the region, but analysts had expected growth of more than 6%.

On the currency markets, the dollar rose to a near seven-year high against the yen, rising above 112 yen to the dollar.

The stronger dollar helped to push the price of oil lower. US crude dipped below $80 a barrel, but recovered to end 46 cents lower at $80.66 a barrel.

Brent crude for December delivery fell 38 cents to $85.86 a barrel.