Stocks, dollar up as central banks accommodative

NEW YORK, Aug 1 (Reuters) - Shares, the dollar and crude oil all rallied sharply on Thursday, with the benchmark S&P 500 stock index closing above 1,700 for the first time, as central banks in the euro zone and Britain joined the Federal Reserve in keeping easy monetary policies intact.

The European Central Bank and the Bank of England both ended policy meetings by leaving interest rates at record lows, a day after the Fed said the U.S. economy still needed its support and avoided any mention of a change to its stimulus measures.