* Markets pricing in more uncertainty -Honeywell, NYSE CEOs
* Investments by US companies likely to be curtailed if no deal reached
* Both CEOs say deal must include tax increases, spending cuts, entitlement reform (Adds background)
By John McCrank
NEW YORK, Nov 13 (Reuters) - U.S. politicians face a stark choice over the next six weeks: come together on a deal to avoid the fiscal cliff, or prepare for a recession as companies seek other places to invest, said the CEOs of NYSE Euronext and Honeywell International Inc.
President Barack Obama and congressional Republicans have sounded conciliatory notes on the fiscal cliff since last week's election, but there is still plenty of scepticism in the business community on the chances of a deal, NYSE's Duncan Niederauer and Honeywell's David Cote told Reuters on Tuesday.
In August 2011, Congress did not agree on raising the U.S. debt ceiling until the last possible minute, leading to massive volatility in equity markets and a downgrade of America's debt rating.
"If the debt ceiling was playing with fire, this is nitroglycerine," said Cote. "If they go off the cliff, I think it would spark a recession that's a lot bigger than economists think. Some think it would just be a small fire. I think it could turn into a conflagration."
Since the election, markets have been focused on the fiscal cliff of steep government spending cuts and tax rises due to be implemented under existing law in early 2013 and the uncertainty surrounding it, along with more long-term fears about the size of the U.S. debt, Big Board boss Niederauer said.
"The next 60 days are critical," he said.
He said the market seemed to be pricing in more uncertainty in the months ahead, and that there could be an upside surprise in store if real progress is made in the lame-duck session of Congress, which would set the table for a credible solution to conquering the debt burden in the following months.
Niederauer said that uncertainty - including around simple things like what the corporate tax rate will be in 2013 - makes it difficult for companies to make plans to invest and hire workers in the United States, further stifling economic growth.
While the economy has struggled since the recession, corporations are sitting on stockpiles of cash and are waiting for a signal as to where to invest, said Niederauer.
If politicians are not able to create some certainty in the markets by putting aside partisan ideas, and making real progress in the next 60 days on fiscal issues, money will likely go elsewhere, both Niederauer and Cote said.
"We simply won't be investing in the United States. We will be investing elsewhere, where we have more certainty of the outcome," Niederauer said.
"Capital is a coward," said Cote of Honeywell, a diversified manufacturer. "You don't go to places that are excessively risky or have more risk in them than you are willing to take."
He said that with many of the world's big democracies - Japan, India, the EU, the United States - in gridlock because of debt, somebody needs to exercise some leadership.
"There is a real opportunity for presidential leadership. That is the one guy in the entire country who could make this argument to the American public and give it to them holistic instead of in pieces," Cote said.
Both Cote and Niederauer said they were optimistic a deal will be reached in time.
Democrats and Republicans generally agree on the need to avoid about $600 billion in deficit-reduction measures set to start in 2013. But they are at odds how to get over the immediate crisis, divided over whether to extend tax cuts for everyone, as Republicans want, or just for those earning below $250,000, as the president wants.
Solving the problem requires "both an increase in taxes and significant entitlement reform, along with discretionary spending cuts if this is going to work, and we need this to work," Cote said.
Both Cote and Niederauer are part of an ad hoc lobby group called Fix the Debt, made up of CEOs pushing for long-term deficit reduction, and Cote is one of several CEOs meeting with President Obama on Wednesday to discuss fiscal issues.
"He (Obama) fully understands the significance of not just the fiscal cliff, but long-term debt, to our economy and what that's doing to hold us back and wants to do something that's going to really make a difference here long-term," he said.
Obama also plans to hold a news conference on Wednesday, during which he will be questioned about negotiations.
Cote said it was not reasonable to expect Congress to come up with the bigger $4 trillion answer by the end of the year. It could, however, put a mechanism in place to develop a simplified tax system that collects more, simplified Medicare/Medicaid that spends considerably less, and discretionary spending cuts, by a specified date such as July 4, he said.
Of the $4 trillion in deficit reduction, which would be phased in over 10 years, Cote said a plan might include $1 dollar in tax increases for every $3 of spending cuts.
There would also need to be a backup - like a Simpson-Bowles, a Domenici-Rivlin, or another $4 trillion debt reduction plan - that would automatically kick in if the plan is not ready by the target date.
Cote, whose name has been brought up by pundits as a potential replacement for Timothy Geithner as Treasury Secretary, said he has not given that role much thought.
"It's nice to be thought about, but I like what I am doing," he said when asked if he would consider the job if offered.
Top executives scheduled to meet with the president on Wednesday include the CEOs of General Electric Co, Wal-Mart, Ford Motor Co, Procter and Gamble Co , American Express, Chevron Corp, International Business Machines, PepsiCo Inc, Xerox Corp, and Aetna Inc. (Editing by Phil Berlowitz and Muralikumar Anantharaman)