The federal government will not be affected if Congress fails to act by July 5.
That leaves the Environmental Protection Agency, Agriculture Department and Energy Department to take the lead on the fight to limit greenhouse gas emissions.
The department, however, will be forced to set up a system for certifying that emissions are within the limits of the agreement, the Associated Press reports.
The EPA, which manages a $5.2 trillion program, will continue to have to manage the program to comply with the Paris accord.
More: EPA says it is in talks with Trump on climate change