Oklahoma governor names energy executive Alan Armstrong to fill vacant US Senate seat

The Williams Companies

24/03/2026 18:13

March 24 (Reuters) - Oklahoma's governor said on Tuesday he was appointing energy executive Alan Armstrong to represent the state in the U.S. Senate, filling a vacancy created after Markwayne Mullin was confirmed as U.S. Homeland Security Secretary.

Governor Kevin Stitt announced Armstrong's appointment in a post on X, calling him a "staunch conservative" who will help advance energy reform efforts.

Armstrong is the executive chairman and former CEO of Williams Companies WMB.N, an energy infrastructure company based in Tulsa, Oklahoma.

"I have no doubt that his perspective will be influential in moving the needle on permitting reform to unlock American competitiveness and energy affordability for generations to come," Stitt said of Armstrong.

Armstrong will replace Mullin until a new senator is elected to fill the seat in November's midterm elections. Armstrong is barred under Oklahoma law from running as a candidate in that election.

The Senate voted 54-45 on Monday to confirm Mullin as Homeland Security Secretary, replacing Kristi Noem. Mullin was scheduled to be sworn in on Tuesday at a ceremony at the White House.

 (Reporting by Ryan Patrick Jones in Toronto; Editing by Andy Sullivan and Bill Berkrot)

 ((ryan.jones@thomsonreuters.com;))