WASHINGTON, Dec 20 (Reuters) - Republicans in the U.S. Congress, while celebrating a major tax bill victory, on Wednesday worked behind the scenes to figure out a way to keep the federal government operating beyond midnight Friday when Washington funding expires.
The House of Representatives was aiming to pass a bill on Thursday that would keep federal agencies humming along at current funding levels through Jan. 19.
But intra-party squabbles had Republicans, who control the House, Senate and White House, searching for the right recipe after they failed to pass a series of regular spending bills for the fiscal year that began on Oct. 1.
The infighting came as Republicans handed President Donald Trump his first major legislative victory with passage of a tax code rewrite.
The most difficult issue in the funding fight, said Republican Representative Tom Cole, is his party's demand that a big increase in defense spending be included in the stop-gap spending bill that is needed by Friday.
It is widely known in Congress that the Senate will not go along with the provision and that negotiators will have to deal with military and non-military spending increases early next year.
Meanwhile, some conservatives do not like the $81 billion price tag that goes with a disaster aid measure that could get tacked on to the temporary spending bill. The money would help Puerto Rico, the U.S. Virgin Islands and several states recover from hurricanes and wildfires.
Other battles include renewing the Children's Health Insurance Program as House conservatives insist on cutting other domestic programs to pay for it. Again, there did not appear to be support in the Senate.
Republican lawmakers insist there will not be a government shutdown beginning on Saturday.
"I can't think of a bigger act of political malpractice after a successful tax reform vote than to shut the government down. Talk about stepping on your own message...but anything is possible around here. This is Congress," moderate Republican Representative Charlie Dent told reporters.
Another tough issue still to be addressed in what could be a catch-all temporary funding bill: an extension of a domestic surveillance law.
In a possible boost for quick action on the temporary spending bill, a bipartisan Senate plan for stabilizing the Affordable Care Act, known as Obamacare, is unlikely to be included. There has been strong House Republican resistance to the idea. (Reporting By Richard Cowan Editing by Chizu Nomiyama)