Passed following President Richard Nixon's refusal to disburse clean water and housing funds, Title X of the Congressional Budget and Impoundment Control Act (2 U.S.C. §§ 681–688) governs how an executive administration must handle congressionally enacted appropriations.

• Rescission (Sec. 1012): Requires the President to request congressional cancellation. If Congress does not pass a rescission bill within 45 days of continuous session, the funds must be made fully available for obligation immediately.
• Deferral (Sec. 1013): Permitted only for programmatic contingencies, reserve efficiency, or specifically authorized statutory conditions. Deferrals for policy disagreements are expressly unlawful.

In Train v. City of New York, 420 U.S. 35 (1975), the Supreme Court held that when Congress passes an appropriation using mandatory language ("shall allocate" or "all sums authorized"), the Executive Branch has no statutory discretion to withhold funds based on presidential policy objections or inflation concerns.

The Comptroller General (head of the Government Accountability Office) independently audits executive apportionment schedules. Under 2 U.S.C. § 687, if the President or OMB fails to release funds after the 45-day rescission period lapses, the Comptroller General is statutorily authorized to bring a civil action in U.S. District Court to compel expenditure.

While the Antideficiency Act prohibits agencies from spending money not yet appropriated by Congress, administrative withholdings that cause appropriations to expire unspent without congressional consent constitute an unlawful impoundment under the ICA, violating Article I, Section 9, Clause 7 (the Appropriations Clause).