US Senate Republican leader Mitch McConnell said on Tuesday it would be "practically impossible" for Congress to pass a supplemental funding package containing aid for Ukraine before Christmas, even if a deal were struck in coming days.
Mr McConnell told reporters that a deal on legislation to aid Ukraine, Israel and the Indo-Pacific will not happen unless president Joe Biden is fully engaged with Senate Republicans in talks aimed at including provisions to restrict migrant crossings at the US-Mexico border.
"(It) is practically impossible - even if we reach an agreement - to craft it, get it through the Senate, get to the House, before Christmas," Mr McConnell told reporters in the US Capitol.
"There won't be a deal until Joe Biden and Republicans reach an agreement," Mr McConnell added. "Without him, there is no deal."
The House and Senate are currently expected to leave Washington on Thursday for their year-end holiday break. The two chambers are due to reconvene during the second week of January.