* Candid remarks were supposed to be private
* Obama says he challenged Republicans on healthcare
* "You think we're stupid?" president says
CHICAGO, April 15 (Reuters) - President Barack Obama gave blunt details of private budget talks with Republicans last week that averted a government shutdown, saying he challenged them to try to repeal his signature healthcare policy.
Obama spoke at length about the private conversations in one of three political fund-raisers for his re-election campaign on Thursday night. His candid remarks came after the White House press pool had been escorted from the room.
His comments were accidentally piped back to the White House and recorded by CBS News and ABC News.
Obama said he firmly rejected Republican attempts to repeal parts of his healthcare overhaul in the budget bill that was eventually approved after anguished negotiations last week.
The president said a staffer for the top Republican, House of Representatives Speaker John Boehner, said Republicans had made concessions and wanted a concession from Democrats.
"And I said to them, let me tell you something: 'I spent a year and a half getting health care passed. I had to take that issue across the country and I paid significant political costs to get it done," he said.
"The notion that I'm going to let you guys undo that in a 6-month spending bill?' I said, 'You want to repeal healthcare? Go at it. We'll have that debate. You're not going to be able to do that by nickel-and-diming me in the budget. You think we're stupid?'"
Obama predicted the same strategy from Republicans would reappear in negotiations over raising the U.S. debt limit.
"This is going to be the strategy going forward -- trying to do things they can do legislatively under the guise of cutting spending," he said.
Obama, who had publicly praised Republicans once a budget deal was reached last Friday to avoid a shutdown, also spoke harshly of Republican efforts to use the budget legislation to defund the family planning organization Planned Parenthood because it also provides abortions.
Obama said he told Boehner and Senate Republican leader Mitch McConnell that they should not try to "sneak this through."
"'You guys want to have this debate? We're happy to have that debate. We will have the debate on the floor of the Senate or the floor of the House. Put it in a separate bill. We'll call it up. And if you think you can overturn my veto, try it,'" he said.
Asked for reaction, Boehner spokesman Brendan Buck said: "The speaker believes his private conversations with the president should remain private. Obviously, if the president chooses to share a self-serving version with campaign donors, that is his prerogative." (Editing by Jackie Frank)