The Environmental Protection Agency will as soon as Monday finalize a scientific finding that greenhouse gases from aviation endanger human health, obligating the United States to regulate emissions from commercial aircraft, sources told Reuters.

The EPA's "endangerment finding" requires the agency to implement greenhouse gas emission standards for U.S. aircraft, which accounts for 11 percent of U.S. transportation greenhouse gas emissions and is one of the largest sources of emissions not yet regulated.

EPA Administrator Gina McCarthy is expected to sign the endangerment finding as soon as Monday, two sources familiar with the process said.