Two senior Republican senators indicated Tuesday that Congress is unlikely to pass a third reconciliation bill this session, raising questions about future defense funding mechanisms.

During a Senate Appropriations Committee hearing on the Air Force's budget for next year, Committee Chair Susan Collins (R-Maine) and Senate Minority Leader Mitch McConnell both expressed skepticism about the prospects for additional reconciliation legislation. The senators cautioned against relying on such a measure for defense funding needs.

The discussion occurred as Collins questioned Air Force Secretary Troy Meink about what she characterized as a low funding request during the Tuesday morning hearing focused on next year's military budget priorities.

Separately, Republican lawmakers are seeking additional details from the Pentagon regarding funding requests related to military operations in Iran. GOP members say they want clearer information about the scope, objectives and costs of the operation before supporting funding measures in what they describe as a challenging election year.

The Iran-related military campaign, which has now exceeded 100 days, has reportedly cost approximately $29 billion according to current estimates. Republicans are calling for more transparency from defense officials about the operation's parameters and financial requirements.

Reconciliation bills allow certain budget-related legislation to pass the Senate with a simple majority rather than the typical 60-vote threshold, making them a key tool for advancing funding measures in a closely divided Congress.