Environmental Protection Agency Administrator Lee Zeldin proposed rolling back parts of the Biden administration’s emission requirements for heavy-duty vehicles, claiming the changes would save truckers up to $12 billion.

Zeldin announced the proposal for heavy-duty engines at the Trump administration’s Great American State Fair on the National Mall in Washington, D.C., on Thursday. The proposal is the latest step in the Trump administration’s efforts to reduce emission standards in the transportation sector on the basis of lowering costs for manufacturers.