Stocks finished sharply lower for a second session Tuesday, with major averages hitting one-month lows, as investors digested comments from President Barack Obama on the ongoing political impasse in Washington.
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In a press conference, President Obama said he has yet to see serious proposals from the Republicans that would allow both sides to resolve their core differences.
"So my suggestion to the Speaker has been and will continue to be: 'Let's stop the excuses, let's take a vote in the House, and let's end this shutdown right now'...There are enough reasonable Democrats and Republicans in the house who are willing to vote 'yes' on the budget that the Senate had already passed."
(Must See: Track the debt payment calendar)
The Dow Jones Industrial Average dropped 159.71 points, or 1.07 percent, to close at 14,776.53, dragged by Visa and IBM. The Dow has tumbled nearly 6 percent since hitting its record high of 15,709.58 on Sept. 18.
The Dow and S&P 500 have fallen for the 11th time in the last 14 trading sessions.
The CBOE Volatility Index (VIX), widely considered the best gauge of fear in the market, jumped above 20. The index has surged nearly 23 percent in October alone.
Most key S&P sectors dropped, dragged by telecoms and materials, while utilities held modest gains.
(Read more: Art Cashin: Why I'm a 'little anxious' now)
"Investors seem to be adding a bit of risk premium in the market because you don't know how this is going to play out—you could actually see the government default," said Paul Zemsky, CIO of multi-asset strategies at ING U.S. Investment Management. "And investors also seem to be adjusting to what the true economic impact will be from the shutdown—it could be anywhere between 0.2 percent and 0.4 percent on GDP per month."
Without an increase to the $16.7 trillion debt limit, the Treasury will lack the funds to pay its debts from late October/early November.
(Read more: No way US would allow debt default? Don't bet on it)
"It's not a high probability event (that the government will default on its debt) but you can't say it's zero anymore," said Zemsky. "But [if it does happen,] everyone's expecting it to be a short default. At the same time, it will erode confidence in the U.S. Treasury market."
Earlier, House Speaker John Boehner said he is willing to negotiate budget issues with President Obama without any conditions.
"I'm not drawing any lines in the sand," Boehner told reporters.
Shortly after the press conference, Boehner's spokesman said Obama called Boehner and reiterated that he would not negotiate on the government funding bill or debt ceiling increase.
(Read more: What is the 'debt ceiling,' anyway? We explain)
In the absence of hard economic data due to the shutdown, investors will focus on the upcoming third-quarter earnings season.
JCPenney spiked higher after the struggling department store chain posted a smaller decline in same-store sales for September, adding it sees positive signs in many areas of its business.
Talisman Energy soared after billionaire investor Carl Icahn Tweeted that he had purchased about 61 million shares of the oil producer and may seek a seat on the company's board.
Also, Nuance rose after Icahn said he had reached an agreement with the speech recognition software maker to seat two of his choices--one being his son Brett--to the company's board of directors.
Meanwhile, two Federal Reserve officials expressed that they wanted the central bank to begin scaling back back asset purchases during their meeting in September. Cleveland Fed President Sandra Pianalto said the improvement in labor market conditions since the Fed launched the program in the fall of 2012 seemed "substantial enough" to support a tapering.
And at a separate event, Philadelphia Fed president Charles Plosser said economic conditions are now in place that should allow the Fed to quickly end its bond purchasing program.
The Treasury auctioned $30 billion in 3-year notes at a high yield of 0.710 percent. The bid-to-cover ratio, an indicator of demand, was 3.05, versus a recent average of 3.35. Benchmark 10-year notes were last down 3/32 in price to yield 2.643 percent. The yields have struggled to break below resistance at around 2.60 percent.
The auction was the first of a $64-billion supply this week. The Treasury will sell $21 billion in 10-year notes on Wednesday and $13 billion of 30-year bonds on Thursday.
Asian shares pared most of their early losses on Tuesday, as mainland Chinese and Hong Kong markets climbed in the first day of trade after the "Golden Week" public holiday.
Shares were lower in Europe meanwhile, with U.K. retailers trading down after the British Retail Consortium reported weaker sales growth. But technology stocks were higher, boosted by a bounce in shares of French company Alcatel-Lucent, which announced the latest part of its cost-cutting plan.
—By CNBC's JeeYeon Park (Follow JeeYeon on Twitter: @JeeYeonParkCNBC)
On Tap This Week:
WEDNESDAY: Mortgage applications, wholesale trade*, oil inventories, 10-yr note auction, FOMC minutes, Nike investor mtg; Earnings from Costco, Family Dollar, Chevron (interim report)
THURSDAY: Jobless claims, import/export prices*, Fed's Bullard speaks, natural gas inventories, 30-yr bond auction, Treasury budget*, Fed's Williams speaks, Fed balance sheet/money supply, chain-store sales, Draghi speech
FRIDAY: PPI*, retail sales*, consumer sentiment, business inventories*, Fed's Rosengren speaks, IMF annual mtg; Earnings from JPMorgan Chase, Wells Fargo
*Data will not be released due to the government shutdown.
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