Idaho Sen. Larry Craig moved to undo his guilty plea to a sex-related charge by filing a motion Monday saying that he was in a “state of fear” and worried about “unnecessary publicity” this summer when he signed the plea.

The motion, filed in court Monday in Hennepin County, Minn., seeks to withdraw the Idaho senator’s plea to disorderly conduct, a charge that arose from accusations he tried to arrange for sex with an undercover police officer in the bathroom of the Minneapolis-St. Paul airport.

In the document, Craig maintained his innocence and said his plea should be withdrawn because when he signed it Aug. 1 “it was not knowingly and understandingly made.”

Rather than seeking advice from a lawyer who would “assist him in publicly fighting these charges,” Craig said in Monday’s court motion that “panic drove him to accept a guilty plea, the terms of which offered him what he thought was a private, expeditious resolution of this matter.”

“I made the decision on that date to seek a guilty plea to whatever charge would be lodged against me,” Craig said in an affidavit filed with the motion.

A spokesman for the Minneapolis-St. Paul airport said that the airport’s prosecutors intend to fight Craig’s attempts to withdraw his plea. They considered it a final judgment when Craig pleaded guilty and paid a $575 fine, said airport spokesman Patrick Hogan.

“There was an arrest, several weeks later there was a plea, and a fine was paid,” Hogan said. “We will object to the motion filed by the senator and vigorously defend the existing plea.”

So far, no date has been set for a hearing, and it’s not clear when Craig would appear in court. Hogan said the airport intends to file a response to Craig’s motion within a week.

Craig’s lead attorney, Washington criminal lawyer Billy Martin, said that the focus of his efforts to undo Craig’s plea will be to prove that what the senator admitted to when he was interrogated by airport police didn’t constitute a crime.

“Sen. Craig admits to going to the bathroom, he admits to moving his foot,” Martin said on NBC’s “Today Show.” “He admits to reaching his hand down. That’s all. That is not a crime. As a matter of law, the conduct that even he admits to does not constitute a crime.”