An Alberta MLA has been formally charged with soliciting prostitutes after he was arrested in a Minnesota sting on Monday.

Fort McMurray-Wood-Buffalo MLA Mike Allen has been charged with one count of hiring, offering to hire or agreeing to hire a prostitute in a public place – a gross misdemeanor in the state of Minnesota.

Police allege in court documents that Allen responded to an online prostitution ad and agreed to meet up with two women, who turned out to be undercover officers, in a St. Paul, Minn., motel room.

Police allege that Allen arrived in a limo and agreed to pay $200 to have sex with the two women.

"The defendant agreed to pay $200 in exchange for sexual intercourse with two women for one hour while wearing a condom," the criminal complaint said. "The defendant placed the cash on the counter and began to undress."

One of the undercover female officers then gave a "bust signal" and another officer entered the room and arrested Allen, says the document.

Allen, 51, was in St. Paul to attend a three-day conference on energy, trade and the environment.

He was one of 13 men arrested in the prostitution sting.

Allen issued a written statement Friday. "I would like to reiterate my apology to my family, my friends, my constituents, my colleagues, my staff, and to all Albertans for the embarrassment I have caused," Allen wrote. "I accept full responsibility for my actions."

Allen has since resigned from Alberta's governing Progressive Conservative caucus and from all legislative committees, but will continue to sit the legislature as an independent.

The opposition Wildrose party wants Allen to resign his seat in the wake of the scandal.

Allen has been ordered to appear in St. Paul court on Sept. 30.

He said he plans to meet with a lawyer to "determine a course of action by the end of next week."