By Rodrigo Campos


NEW YORK (Reuters) - The S&P 500 and Nasdaq Composite fell on Monday after six sessions of gains, weighed by tech sector stocks, while a rally in energy shares petered out as crude oil gains withered.


Bank shares fell ahead of the Federal Reserve's last meeting for the year, set to begin Tuesday and expected to end on Wednesday with the year's first interest rate increase.


Traders cashed in gains in bank stocks ahead of the meeting, even if a rate hike, which on paper would benefit banks, is all but priced in.


The chances that the U.S. central bank will not raise rates is "close to zero, but it's not zero," said Kim Forrest, senior equity research analyst at Fort Pitt Capital Group in Pittsburgh.


The S&P 500 financial sector <.SPSY> fell 0.9 percent following five consecutive weeks of gains.

The benchmark's tech sector <.SPLRCT> fell 0.5 percent after posting its largest weekly advance in a year last week.

The healthcare sector was the biggest boost to both the S&P 500 and the Dow industrials.

Regeneron <REGN.O> gained 3.8 percent to $387.10 after data on a competing drug combination from Novartis <NOVN.S> and Opthotech <OPHT.O> did not meet its main goal. Ophthotech shares tumbled 86.4 percent.

Regeneron was the largest percentage gainer on both the S&P 500 and the Nasdaq 100.

The Dow Jones industrial average <.DJI> rose 39.58 points, or 0.2 percent, to 19,796.43, the S&P 500 <.SPX> lost 2.57 points, or 0.11 percent, to 2,256.96 and the Nasdaq Composite <.IXIC> dropped 31.96 points, or 0.59 percent, to 5,412.54.

The Dow posted the latest in a string of record closing highs.

Energy stocks on the S&P 500 <.SPNY> rose as much as 2.5 percent in early trading as crude oil prices soared around 6 percent to levels not seen in a year and a half. The sector ended up 0.7 percent, with both WTI <Clc1> and Brent crude <LCOc1> barrels up less than 2 percent.

The industrials <.SPLRCI> sector was down 0.37 percent, dragged down by defense stocks. Lockheed Martin <LMT.N> declined 2.5 percent to $253.11, bouncing back from a session low of $245.50, after U.S. President-elect Donald Trump tweeted that the company's F-35 program and costs were "out of control."

Viacom <VIAB.O> fell 9.4 percent to $34.99. National Amusements withdrew its merger proposal for CBS <CBS.N> and Viacom. Privately-held National Amusements is controlled by Sumner Redstone and his daughter, Shari Redstone.

Alexion Pharmaceuticals <ALXN.O> fell 12.9 percent to $115.08. The chief executive officer and chief financial officer resigned, a month after the drugmaker said it was investigating allegations related to sales practices of its flagship drug.

Declining issues outnumbered advancing ones on the NYSE by a 1.79-to-1 ratio; on Nasdaq, a 2.23-to-1 ratio favored decliners.

About 7.4 billion shares changed hands in U.S. exchanges, roughly in line with the average volume over the last 20 sessions.

(Reporting by Rodrigo Campos; Editing by Jonathan Oatis)