An Alberta MLA will know by the end of the week whether he will face charges -- and potentially jail time -- after his arrest this week in a Minnesota prostitution sting.

Fort McMurray-Wood-Buffalo MLA Mike Allen was arrested by police in St. Paul, Minn., on Monday night after he responded to an online prostitution ad and agreed to meet up with two women who turned out to be undercover officers.

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

St. Paul attorney Sara Grewing told the Canadian Press her office is reviewing Allen's file for a possible gross misdemeanour charge of solicitation of prostitution.

A conviction would typically come with a 90-day jail term and $1,000 fine, but a first offender could be handed a much lighter sentence.

Allen was one of 13 men netted in the sting after police posted the online ad offering sexual services for cash in St. Paul, Minn.

Arriving at the Edmonton airport overnight Tuesday, Allen said he had resigned from Alberta's governing Progressive Conservative caucus and from all legislative committees, but will continue to serve on the legislature as an independent -- at least for now.

"At this point I've removed myself from caucus and any legislative committees and I'll be taking some time to reflect on that," he told CTV Edmonton.

Allen said "I truly regret everything that has occurred," adding that he was happy to be home and was waiting to see whether charges would be laid.

He added: "I truly regret that this happened, I have no excuse for my actions, just that it's occurred. I'm here to face the music."

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

"For an MLA to behave in this manner while travelling abroad on government business is unacceptable and he owes it to the people of Fort McMurray and all Albertans to immediately resign," Wildrose Leader Danielle Smith said in a news release.

Allen said in a statement that he takes full responsibility for his actions.

"I apologize to my family, friends, my constituents, my colleagues, my staff and to all Albertans for the embarrassment I have caused and for failing to live up to the standards expected of me and the standards I expect of myself," he said in the statement released Tuesday.

"I made this mistake of a profound lapse of personal judgment. It is my mistake, for which there is no excuse, and for which I accept full responsibility."

Tory whip Steve Young said Allen called him Tuesday morning to tell him about the arrest and offered his resignation -- which he accepted.

"We have a great caucus, we have great people. Mike is a great person but sometimes people do dumb things so I think this is a shock. We expect the highest standards from all our caucus colleagues and this certainly put that into question," Young said.

Allen, a jazz musician who formerly owned a music store in Fort McMurray, was appointed as a special advisor to the minister of transportation in 2012, chaired a conflict of interest committee, and sat on four other committees as well as the Treasury Board before resigning from those positions following his arrest.