* Inflation to likely rebound -Fed's Fischer * Oil prices jump more than 5 pct * Phillips 66 (NYSE: PSX - news) up after Buffett discloses stake * Indexes finish down: Dow 0.69 pct, S&P 0.84 pct, Nasdaq 1.07 pct (Updates to close) Aug 31 (Reuters) - Wall Street ended lower on Monday and wrapped up its worst month since 2012 after a senior Federal Reserve official heightened fears among investors of a potential U.S (Other OTC: UBGXF - news) . interest hike in September. Fed Vice Chairman Stanley Fischer on Saturday said U.S. inflation would likely rebound as pressure from the dollar fades, allowing the Fed to raise interest rates gradually. Many analysts took Fischer's comments as a sign the Fed would raise rates in September, instead of December. That shook investors who were already jumpy after weeks of turbulence caused by concerns about a stumbling Chinese economy. "What you see in the market today is caused by Fischer's comments over the weekend. If they move in September, it's going to cast a lot of doubt about where they will... More