* GE weighs on S&P after reporting negative cash flow
* Trump says tax plan to be revealed next week
* First round of French election to be held on Sunday
* Dow up 0.05 pct, S&P 500 down 0.14 pct, Nasdaq down 0.08 pct (Updates to mid-afternoon, changes byline)
By Chuck Mikolajczak
NEW YORK, April 21 (Reuters) - U.S. stocks edged lower on Friday as investors exercised caution ahead of the first round of the closely contested French presidential election, although the S&P 500 remained on track for its first weekly gain in three.
The first round of France's presidential election may be too close to call when polls close on Sunday because initial projections will not be available as early as in the past, pollsters and their watchdog said.
Most polls see centrist Emmanuel Macron and far-right leader Marine Le Pen qualifying on Sunday for a May 7 runoff, but conservative Francois Fillon and leftist Jean-Luc Melenchon are not far behind and within the margin of error.
"After Brexit everyone has to be concerned," said Joe Saluzzi, co-manager of trading at Themis Trading in Chatham, New Jersey, referring to the surprise vote in June by the United Kingdom to leave the European Union.
"People are not going to trade if they are nervous nowadays - there is a little nervousness, a lot of uncertainty, so let’s wait and see."
Stocks pared losses after U.S. President Donald Trump told the Associated Press he would reveal a tax plan next week.
A steady stream of strong earnings through the week continued to bolster market sentiment.
Of the 95 companies in the S&P 500 that have reported earnings through Friday morning, about 75 percent have topped expectations, according to Thomson Reuters data, above the 71 percent average for the past four quarters.
Overall, profits of S&P 500 companies are estimated to have risen 11.2 percent in the quarter, the best since 2011.
The Dow Jones Industrial Average rose 14.07 points, or 0.07 percent, to 20,592.78, the S&P 500 lost 3.03 points, or 0.13 percent, to 2,352.81 and the Nasdaq Composite dropped 3.52 points, or 0.06 percent, to 5,913.26.
Shares of General Electric fell 2.2 percent to $29.61 after the company reported negative cash flow from its industrial operations in the first quarter. The stock was the biggest drag on the S&P 500.
Schlumberger lost 2.3 percent at $74.76 after the oilfield services provider warned that margins would remain under pressure as it spends more to bring back idled equipment.
Mattel fell as much as 11.8 percent to an 18-month low of $22.22 after the toymaker reported a bigger-than-expected quarterly loss.
Federal Reserve Vice Chair Stanley Fischer told CNBC that the central bank remains on track for two more interest rate increases this year despite some soft economic data recently.
Declining issues outnumbered advancing ones on the NYSE by a 1.09-to-1 ratio; on Nasdaq, a 1.22-to-1 ratio favored decliners.
The S&P 500 posted 27 new 52-week highs and 1 new low; the Nasdaq Composite recorded 79 new highs and 35 new lows.
(Reporting by Chuck Mikolajczak; Editing by Nick Zieminski)