House Speaker John Boehner on Sunday flatly refused to schedule votes for full government funding or to raise the debt ceiling without concessions from Democrats, asserting that the House couldn't and shouldn't take either step without addressing problems with the new health care law and the nation's debt crisis.

In an exclusive interview on ABC's "This Week with George Stephanopoulos," Boehner said he does not know how and when the current standoffs will end.

But he made clear that, in his view, President Obama and Democrats in Congress are to blame for both the government shutdown and the possibility that the United States will default on its debt. The speaker reiterated his demand for negotiations with the president to find a path forward on both fronts.

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"The American people expect in Washington when we have a crisis like this that the leaders will sit down and have a conversation. And I told my members the other day that there may be a back room somewhere, but there's nobody in it," said Boehner, R-Ohio.

"We're interested in having a conversation about how we open the government and how we begin to pay our bills. But it begins with a simple conversation."

The president has said no talks are possible until government operations are fully funded again, and has ruled out entirely negotiations over the debt ceiling.

If the government shutdown lasts longer, and if the nation defaults on its debt, Boehner said blame should fall on the president: "I'm willing to sit down and have a conversation with the president. But his refusal to negotiate is putting our country at risk."

While a growing number of his colleagues have expressed frustration with the House GOP strategy, Boehner gave no ground in continuing his push for changes to the president's health care law, as well as broader fiscal reforms, in the current fights.

Some 21 House Republicans have said publicly that they're willing to support a "clean" measure to extend all government funding without other conditions attached, according to ABC News' count. That's apparently enough, when added to Democratic votes, to pass a bill out of the House.

But the speaker disputed that notion: "There are not the votes in the house to pass a clean CR."

Boehner also appeared to back off of private assurances he's offered colleagues that the nation would not default on its debt. Treasury Secretary Jack Lew has said the nation will run out of ways to continue to pay all of its bills Oct. 17, making an increase in the debt limit an urgent priority.

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Boehner said repeatedly that he does not intend to have the nation default on its debt. But he declined to guarantee that he'd bring a debt-limit bill to the floor of the House without concessions from Democrats.

"The nation's credit is at risk because of the administration's refusal to sit down and have a conversation," he said. "The votes are not in the House to pass a clean debt limit. And the president is risking default by not having a conversation with us…. We're not going down that path. It is time to deal with America's problems. How can you raise the debt limit and do nothing about the underlying problem? "

Asked by Stephanopoulos whether that no negotiations means the country will default on its debt, Boehner responded: "That's the path we're on. Listen, the president canceled his trip to Asia. I assumed, well, maybe he wants to have a conversation. I decided to stay here in Washington this weekend. He knows what my phone number is. All he has to do is call."

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Boehner acknowledged that the showdown over government funding, aimed at scaling back the Obama health care law, isn't a fight that he chose. He also appeared to confirm that, in conversations with Senate Majority Leader Harry Reid, he had previously sought to ensure full government funding, only to be convinced to take a different course after consulting with his fellow House Republicans.

"I and my members decided that the threat of Obamacare and what was happening was so important that it was time for us to take a stand. And we took a stand," he said. "I thought the fight would be over the debt ceiling. But you know, working with my members, they decided, well, let's do it now. And the fact is, this fight was going to come, one way or the other. We're in the fight."

Boehner suggested that he'd like negotiations with the president to include entitlement reform. But he ruled out including new tax revenues as part of a deal.

J. Scott Applewhite/AP Photo

"The president got … $650 billion of new revenues on January the 1st. He got his revenues. Now, it's time to talk about the spending problem," he said. "Very simple. We're not raising taxes."

Responding to Boehner's appearance, Sen. Charles Schumer, D-N.Y., challenged Boehner to test his claim that the votes aren't there to reopen the government.

"Let me issue him a friendly challenge: put it on the floor Monday or Tuesday," Schumer said on "This Week." "Speaker Boehner, just vote."

He also rejected Boehner's request for negotiations until or unless House leaders agree to end the shutdown and raise the debt limit.

"This is playing with fire. And we are happy to negotiate, but we want to negotiate without a gun to our head," Schumer said.

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