WASHINGTON » The government unlocked its doors today after 16 days, with President Barack Obama saluting the resolution of Congress’ bitter standoff but lambasting Republicans for the partial shutdown that he said had damaged the U.S. economy and America’s credibility around the world.

"There are no winners here," Obama said just hours after signing a last-minute measure from Congress that was free of the Republican demands that had started the showdown. The deal allowed federal workers to return this morning and headed off the threat that the nation would default on its debts, at least for this year.

"The American people are completely fed up with Washington," Obama said in stern remarks at the White House. The nation’s credit rating was jeopardized, economic growth and hiring were slowed and federal workers were temporarily deprived of paychecks, Obama said, all because of "yet another self-inflicted crisis."

In hopes of averting another standoff when the just-passed measure runs out, Congress’ four top budget writers met over breakfast to begin new talks on spending and borrowing issues that have bedeviled the divided government for years.

Obama warned lawmakers about disagreements so bitter they could "degenerate into hatred" and urged a shift toward cooperation. He called for Congress to come up with a long-term agreement for restraining Medicare and Social Security spending and to pass immigration and farm and food bills that have floundered amid partisan disputes.

He also sought to assure governments and investors around the world that the "full faith and credit of the United States remains unquestioned."

"We’ll bounce back from this," Obama declared. "We always do."

The House and Senate voted late Wednesday night to end the shutdown that began when Republicans tried unsuccessfully to use must-pass funding legislation to derail the president’s landmark health care law.

Early today, Obama signed the measure and directed all agencies to reopen promptly. The government unlocked office doors, carried barriers away from national monuments and lifted entrance gates at parks across the county.

The relief felt by furloughed federal employees was tempered by worry that the truce might not last much past the holidays. Congress approved government funding only through Jan. 15.

To head off a default, the package gives the government the authority to borrow what it needs through Feb. 7. Treasury officials will be able to use bookkeeping maneuvers to delay a potential default for several weeks beyond that date, as they have done in the past. Among the maneuvers, officials can suspend contributions to one of the pension plans used by federal retirees.

In the meantime, lawmakers will try to find agreement on how to replace this year’s across-the-board spending cuts with more orderly deficit reduction.

"I hope this is the end of this," said Vice President Joe Biden, who greeted workers returning to the Environmental Protection Agency with hugs, handshakes and muffins. But Biden acknowledged, "There’s no guarantees of anything."

The small group of lawmakers tasked with steering Congress out of three years of budget stalemates and standoffs offered no promises.

House Budget Committee Chairman Paul Ryan, R-Wis., said the group’s goals were "to get this debt under control, to do smart deficit reduction and to do things that we think will grow the economy and get people back to work."

"We believe there is common ground," Senate Budget Committee Chairman Patty Murray, D-Wash., said after their meeting.

The impasse furloughed about 800,000 workers at its peak, before civilian Defense Department employees were called back. It closed down most of NASA, the Environmental Protection Agency and the Interior Department and halted work not considered critical at other agencies.

"We’re back from the #shutdown!" the Smithsonian Institution crowed on Twitter, announcing that museums were reopening today. The U.S. Capitol’s visitor center planned to resume tours. "Closed" signs started coming down at national parks and offices across the nation, hours after the deal was sealed in Washington.

Congress agreed to pay federal workers for the missed time. No such luck for contractors and all sorts of other workers whose livelihoods were disrupted.

"More business. More money," cab driver Osman Naimyar said happily, noting the growing crowds of commuters on Washington streets. He lost about a fifth of his normal fares, he said, while federal workers stayed home and tourists disappeared from the National Mall.

The financial services company Standard & Poor’s estimated the shutdown drained $24 billion out of the economy, and it can’t all be recouped. That’s about $75 for each U.S. resident. Fitch credit rating agency is reviewing its AAA rating on U.S. government debt for a possible downgrade.

Obama and his Democratic allies on Capitol Hill were the decisive victors in the fight, which was sparked by tea party Republicans including Sen. Ted Cruz of Texas. They prevailed upon skeptical GOP leaders to use a normally routine short-term funding bill in an attempt to "defund" the 2010 health care law known as "Obamacare."

"We fought the good fight. We just didn’t win," House Speaker John Boehner, R-Ohio, conceded. He was given positive reviews from Republicans for his handling of the crisis, though it again exposed the tenuous grasp he holds over the fractious House GOP conference.

The shutdown sent approval of the GOP plummeting in opinion polls and exasperated veteran lawmakers who saw it as folly.

"It’s time to restore some sanity to this place," House Appropriations Committee Chairman Harold Rogers, R-Ky., said before the vote.

The agreement was brokered by the Senate’s top Democrat, Majority Leader Harry Reid of Nevada, and its Republican leader, Mitch McConnell of Kentucky. They stepped in after the House was unable to coalesce around a Republican-only approach.

McConnell is up for re-election next year, and the tea party opponent he faces in the Republican primary issued a statement criticizing him for making the deal.

"When the stakes are highest, Mitch McConnell can always be counted on to sell out conservatives," Matt Bevin said.

The Senate approved the legislation by an 81-18 vote. The House followed suit by a tally of 285-144, with 87 Republicans in favor and 144 against. Democrats unanimously supported the bill, even though it kept across-the-board funding cuts they opposed.

Associated Press writers Alan Fram, Jessica Gresko and Connie Cass contributed.