WASHINGTON — The weak economy and the mammoth costs of helping the savings and loan industry will soon push the federal deficit to records surpassing $300 billion per year, a congressional study said today.

But by 1993, the newly enacted deficit-reduction law and an improving economy should begin shrinking the federal shortfall, the Congressional Budget Office said in a report presented to the House Budget Committee.

The calculations are the first showing how the five-year, $496-billion deficit-cutting law will affect the federal budget over the next several years. The Bush Administration is not expected to release its own figures until February.