Republican senators with competing bills to tackle the National Park Service’s $12 billion deferred maintenance backlog, which has been identified as a top priority for the Trump administration, reached a compromise Friday on a single measure.

The bill from Sens. Rob Portman, R-Ohio, and Lamar Alexander, R-Tenn., takes pieces from each of the senators’ previous bills to create a new trust fund to pay for national park improvements with revenue from energy production on federal lands.

With endorsements from Interior Secretary Ryan Zinke and leading parks advocacy groups such as the National Parks Conservation Association, the new legislation has momentum to move through Congress.

Co-sponsors include Sens. Mark Warner, D-Va., Angus King, I-Maine, Shelley Moore Capito, R-W.Va., and Cory Gardner, R-Colo.

“For more than a century, the National Park Service has been inspiring Americans to explore the natural beauty of our country,” Portman said in a statement. “But in order to keep that work going, we need to ensure that they have the right resources to maintain our national parks.”