The pressure is on for the U.S. House of Representatives, whose lawmakers are meeting Saturday in another effort to pass a federal budget and avoid a government shutdown.
Congress has until Monday at midnight to approve a bill providing funds to keep the government running from October 1 onward.
The Republican-controlled House has already rejected a bill the Senate sent Friday that would keep the government running through November 15. That bill did not include a provision to defund President Barack Obama's health care reform law, a goal of many Republican lawmakers.
The House is now set to vote later Saturday on its own version of the budget, which would delay the health care law for a year and repeal a tax on medical devices. The plan would fund the government through mid-December. But Democratic Senate Majority Leader Harry Reid has already vowed the Senate will reject it. Senate Democrats have insisted they will not pass a bill that alters the health care law, also known as the Affordable Care Act, or "Obamacare."
House Republicans also plan to pass legislation ensuring U.S. troops are still paid in the event of a shutdown.
If the two houses of Congress cannot make the Monday at midnight deadline, hundreds of thousands of federal workers will be temporarily laid off and many government programs halted.
Lawmakers from both parties engaged in a spirited House debate Saturday, urging each other to make compromises.
On Friday, President Obama told White House reporters that Republicans in the House should stop what he called "political grandstanding'' and approve a temporary government funding measure without tying it to efforts to gut the new health care law.
The Speaker of the House of Representatives, Republican John Boehner, accused the president of "grandstanding" himself, saying Mr. Obama has refused to even be part of the process.
Another deadline also looms -- October 17 -- when Congress must vote to increase the government's borrowing authority. If no agreement is reached by then, the United States could default on its debts for the first time ever.
President Obama said Friday that a failure by Congress to increase the so-called "debt ceiling" would have a "profound destabilizing effect" on the U.S. and world economies.
Some Republican leaders fear a partial shutdown of the federal government would hurt the party's standing heading into next year's congressional elections. A government shutdown in the mid-1990s, when Republicans controlled both houses of Congress, was followed by the re-election of then-president Bill Clinton in 1996.