(Reuters) -U.S. railroad operator Norfolk Southern ( NSC ) said Chairman Claude Mongeau resigned from the company's board on Tuesday, citing personal reasons.

Mongeau had been an independent director on Norfolk's board since 2019, and was appointed chairman in May last year. He had previously served as president and chief executive for Canadian National Railway from 2010 to 2016.

The board will elect a new chair at its next meeting later this month, the company said.

Mongeau is currently also a director at Canadian oil and gas firm Cenovus Energy.

Norfolk had agreed to add an independent member to its board last year, settling a long-drawn battle with activist investor Ancora Holdings over the company's governance.