NEW YORK, Nov 14 (Reuters) - World stocks fell on Wednesday, with U.S. stocks closing at their lowest levels since the summer as investors focused on the coming battle over the U.S. "fiscal cliff," while oil prices gained on an escalation of violence in the Middle East. The Dow industrials and the Nasdaq hit lows not seen since late June, while the broad S&P 500 ended at its lowest since late July. The pace of the U.S. stock market's sell-off accelerated following President Barack Obama's first press conference since re-election, where he reiterated his call for the wealthy to pay higher taxes. Brent crude oil ... (full story)