Nexstar Media Group Inc. agreed to buy TV station operator Tegna Inc. for $3.5 billion in a deal that stands to dramatically expand Nexstar’s reach and test the Trump administration’s appetite for regulatory reform.

To close the deal, Nexstar will need approval from the Federal Communications Commission, which could cement its position as the biggest provider of local TV in the U.S.

Irving-based Nexstar Media has agreed to buy smaller rival Tegna for $3.54 billion, creating a local-TV powerhouse that seeks to compete better with big