Filner, D-Calif., offered few details of the Aug. 19 incident in a three-sentence statement issued after he returned from a week in Iraq.
"I was tired after a delayed flight and frustrated by the subsequent further delay of the entire flight's baggage. But I did not want things to turn out as they did, with offense obviously taken and much misunderstanding," the statement said.
"This is an episode that I regret and hope to move beyond."
His spokeswoman, Amy Pond, didn't immediately return messages seeking additional information.
Filner allegedly attempted to enter an employees-only area, pushed aside an employee's arm and wouldn't leave when asked, according to Courtney Prebich, assistant media relations manager for the Metropolitan Washington Airports Authority.
Filner had disputed accounts of the incident as "factually incorrect" and said the charges were "ridiculous," but he didn't elaborate on that in his statement Wednesday.
The female employee, whom United declined to identify, did not require medical attention. However she decided to press charges and a Loudoun County, Va., magistrate issued a summons for Filner to appear on misdemeanor assault and battery charges in Loudoun County General District Court on Oct. 2.
As of Wednesday Filner had not been served with the summons because it must be delivered to him directly, Prebich said. She said airport authorities were in touch with Filner's attorney.
Filner is an eight-term incumbent who chairs the Veterans Affairs Committee and represents a San Diego-area district bordering Mexico.