Congressional negotiators resolved policy disputes to reach a deal for a $1.1 trillion spending Bill on Tuesday but still expected to need a stop-gap extension to avoid a US government shutdown at midnight on Thursday.
House of Representatives Republicans were preparing to pass a short-term funding extension of one to two days to allow the Senate more time to clear procedural hurdles that could drag final passage past the deadline.
The snags added some drama to a spending bill that appeared to be cruising toward passage, despite demands from conservative Republicans to withhold spending from President Barack Obama's immigration order, which would allow millions of undocumented immigrants to stay and work in the United States.
Final hurdles on the massive bill were cleared when some controversial financial services provisions were removed to be dealt with separately.
The measure aims to fund all government agencies through September 2015, except for the Department of Homeland Security, which would be extended only through late February, providing Republicans leverage over the agency implementing the Obama immigration order.
A bipartisan provision aimed at shoring up distressed multi-employer pension plans and the government fund that guarantees them was taken out of the bill and proposed as an amendment that would get a separate vote. It would raise insurance premiums for these plans and allow them to reduce benefits for non-disabled beneficiaries under age 75, among other changes.
Full details of the bill were expected to be published on Tuesday evening.
Senate Democratic leader Harry Reid said he believed it would be difficult for lawmakers to keep out proposed language restricting the District of Columbia's new marijuana legalisation law.
The "omnibus" funding bill will keep domestic spending largely flat with last year and provide emergency funds to fight the Ebola outbreak in West Africa. Current government spending authority expires at 12:01 a.m. EST (0501 GMT) on Friday.
A six-year extension for a federal terrorism insurance backstop that was created after the September 11, 2001, attacks was also excluded from the funding bill and is being dealt with separately.
Democrats had been battling over the past two days to try to exclude a Republican-authored provision to prevent new restrictions on derivatives trading by large banks from taking effect. The language would give banks a reprieve from rules that would require them to move derivatives trading away from units that benefit from federal deposit insurance and Federal Reserve loans.