Lawmakers are expected to start the difficult task this week of determining which of the credits are on the chopping block to help pay for the GOP's budget bill.
The Greenhouse Gas Reduction Fund is at the center of a fight between the Trump administration and environmental groups seeking access to the funds that Congress approved under its massive climate legislation.
"Every president in American history has the right to have his or her own advisers," Republican Texas Rep. Randy Weber said at a POLITICO Playbook event.
Since 2010, the National Park Service has seen staffing levels plummet even as visitation climbed. Further cuts could hamper the busy summer season, staffers and advocates warned.