The U.S. Supreme Court won’t hear a St. Louis-based natural gas company’s appeal of a lower court’s decision that could close a pipeline that runs through parts of Illinois and Missouri.

The court rejected Spire Inc.’s appeal Monday without comment. Spire President Scott Smith pledged to fight to keep the pipeline operational.

The Federal Energy Regulatory Commission granted approval for the pipeline in 2018 and it became fully operational in 2019. The pipeline connects with another pipeline in western Illinois and carries natural gas to the St. Louis region.

A 2020 lawsuit filed by the Environmental Defense Fund called the pipeline unnecessary and harmful to land in its path.