The House Ethics Committee will consider an investigation of Oklahoma Republican congressman Markwayne Mullin.
A spokeswoman for the congressman says Mullin is cooperating.
"Congressman Mullin is cooperating with the House Ethics Committee and believes he is in full compliance with all ethics rules. There will be no further comment at this time."
Ethics Committee chairman Michael Conaway and ranking Democrat Linda Sanchez said Thursday they had received a referral about Mullin from the Office of Congressional Ethics.
The OCE is an outside organization that can refer cases to the House Ethics Committee. The subject of the potential investigation isn't being disclosed.
Conaway and Sanchez say that considering an investigation does not indicate any violation has occurred. They will announce any further action by March 24.
The Associated Press contributed to this report.