Obama went to Martha's Table in Washington, which helps low-income children and families, to meet with furloughed federal employees who've been helping out at the facility.
"This week if we don't start making some real progress, both the House and the Senate and if Republicans aren't willing to set aside their partisan concerns in order to do what's right for the country, we stand a good chance of defaulting and defaulting could have a potentially have a devastating effect on our economy," Obama said.
Recognizing volunteers who were federal workers furloughed because of the government shutdown Oct. 1, Obama said, "these are folks who have not been paid in some cases, are very eager to be back on the job, but are not even allowed to work. And yet they're here contributing, giving back to the community."
Obama walked around the food preparation area wearing a green apron, stopping at several tables where volunteers and staff assembled food.
He spoke to elementary students from Sidwell Friends school who were making peanut butter and jelly sandwiches and some furloughed feds making yogurt parfait and bologna sandwiches.
"Can I just say just in the few moments I've been here I'm feeling a little sticky," Obama said. "I think I got some PB&J on my fingers."
Obama noted that there has been progress in the Senate "with Republicans recognizing it's not tenable, it's not smart, it's not good for the American people to let America default."
"There's been some progress in recognizing that we're not going to be able to completely bridge the differences between the parties all at once," he said. "And so it doesn't make sense in the meantime to try to use a shutdown or the threat of default as leverage in negotiations."
Obama postponed a meeting with bicameral, bipartisan leaders Monday afternoon after Senate Majority Leader Harry Reid presented a plan to Senate Minority Leader Mitch McConnell that would reopen government until mid-to-late December and extend the debt ceiling until next year.
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