Republicans and Democrats are clashing over the use of a so-called war fund to bypass federal budget caps that were imposed in 2011.
Congressional Republicans have drafted defense policy and spending bills that adhere to spending caps, but funnel an extra $89 billion to the military through the Overseas Contingency Operation account.
Democrats oppose using the fund to skirt the spending limits, arguing that funding should be increased for both the military and domestic programs. President Obama has threatened to veto any spending bills that adhere to the caps.