WASHINGTON — Congress is bracing this month for another round of bitter spending battles over President Trump’s promised border wall and his immigration agenda, with only three weeks remaining before the government runs out of money.

With the memory of the nation’s longest government shutdown still fresh in their minds, White House officials and congressional leaders are pushing for a temporary agreement in the coming weeks to hold off a funding breach and allow more time to resolve the thorniest issues. But as senators meet on Tuesday for only the second time this year to debate the entire federal spending picture, the race to reconcile at least a fraction of the 12 necessary bills is particularly charged, even by the usual standards of the divided Congress.

“You always try and get things done as efficiently as we can,” Representative Nita M. Lowey, Democrat of New York and the chairwoman of the House Appropriations Committee, said on Monday. “But there are a lot of factors.”

Ms. Lowey huddled Monday afternoon with Speaker Nancy Pelosi; Senator Chuck Schumer of New York, the Democratic leader; and Senator Patrick J. Leahy of Vermont, the top Democrat on the Appropriations Committee, to begin discussing how to proceed.