. The congressional supercommittee seeking a long-term debt-reduction deal over at least $1.2 trillion in deficit cuts remains deadlocked over Democrats' insistence on tax increases as a deadline for agreement nears. (Andrew Harrer/BLOOMBERG)

President Obama called the Democratic and Republican chairmen of Congress’s special deficit reduction supercommittee Friday and urged them to reach a deal, as the panel’s deadline for agreeing on a strategy to slash the nation’s debt rapidly approaches.

In separate phone calls, Obama urged Sen. Patty Murray (D-Wash.) and Rep. Jeb Hensarling (R-Tex.) to find a way to steer the 12-member bipartisan panel to an agreement, the White House said.

But he also carried another message: Congress should not undo the painful consequences for failing to reach a deal that were agreed to when the supercommittee was created in the August debt deal.

According to that agreement, if the committee of six senators and six representatives deadlocks, budgets will be cut automatically by $1.2 trillion over the next decade.

Half of those cuts would come from the Pentagon, a prospect daunting enough that leading lawmakers have suggested the cuts should be repealed.

But the so-called sequester could not be undone without a sign-off from Obama, and he made clear Friday that he would not agree.

“The sequester was agreed to by both parties to ensure there was a meaningful enforcement mechanism to force a result from the Committee,” the White House said in a statement. “Congress must not shirk its responsibilities. The American people deserve to have their leaders come together and make the tough choices necessary to live within our means, just as American families do every day in these tough economic times.”

In a statement, the White House indicated that Obama was seeking an update on the process as a Nov. 23 deadline for cutting at least $1.2 trillion from the nation’s deficit over the next 10 years looms.

He urged them to strike a deal that would cut both entitlements and raise revenues.

Obama has faced criticism for not being more engaged with the ongoing congressional talks. He made the calls from Air Force 1, en route to Hawaii for an economic conference. It’s the first stop on a weeklong trip that will also take Obama to Australia and Bali; he won’t return until Nov. 20 — just days before the committee’s Nov. 23 deadline.

Earlier this week, Republicans on the panel advanced a plan to cut deficits by $1.2 trillion that included $350 billion in new revenues, derived largely from a revision to the tax code that would limit some deductions and subsidies while also lowering the top tax rate to 28 percent.

Democrats said the proposal matched deep spending cuts with too little new revenue and would result in a dramatic tax cut for the wealthy. They countered with an offer to cut deficits by $2.3 trillion, in part by raising $1 trillion in new taxes. Republicans said they could not accept tax increases of that size.

But both sides say negotiations are continuing, and the two sides have been trading ideas.

“We’re continuing to have conversations, batting around a lot of ideas,” said Rep. Chris Van Hollen (D-Md.), a member of the panel, as he emerged Thursday evening from an hour-long huddle with fellow supercommittee member Sen. Jon Kyl (R-Ariz.). “Everyone’s still focused on trying to get an agreement.”

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