North St. Paul City Council Member Scott Thorsen said all along that if Mayor Mike Kuehn didn't quit, he would.

So when Kuehn refused to resign after an ugly incident a few weeks back in which he challenged Thorsen during a council workshop to step "outside" to settle their differences, Thorsen did what he said he'd do — he resigned.

"If [Kuehn] would've resigned, I would've stayed on," Thorsen said Wednesday, a day after announcing his decision at a City Council meeting. "He's the one that threatened me, and I'm the one that's walking away. It just doesn't make sense, but it's just the way it played out, I guess."

The trouble between the men started at the work session earlier this month as the two discussed liquor ordinances before a regular council meeting. After their exchange got testy, Kuehn, 64, challenged Thorsen, 31, to take it "outside." Although both said last week they had no intention of coming to blows, Thorsen said he saw no way the two could coexist in what had become "a hostile working environment."

And so, he said, one of them had to go.

Thorsen said again Wednesday that he resigned because he no longer feels comfortable working with Kuehn.

"It's over with," he said.

Kuehn did not return phone calls or e-mails Wednesday. But he said last week that he was "terribly embarrassed and sorry for losing my temper for a short period of time" and hoped that Thorsen would not resign.

"In politics, you kind of lose it a little bit," Kuehn said then. "But there is no reason for me to step down and walk away from 25 years of work I have done."

Thorsen, who narrowly lost to Kuehn in last November's race for mayor, said he believes that Kuehn's mayoral title doesn't give him the right to bully colleagues, which is why he decided to make his resignation public.

"How are people supposed to know the truth?" he said. "That's why I publicly came out to say, 'Hey look, this happened.' "

Still, city officials are hoping Thorsen will reconsider. Council Member Candy Petersen said the council will hold a meeting later this month with a mediator to defuse the situation.

"We didn't accept [his resignation], so we're going to have an emergency workshop so we can discuss all of this, and hopefully he'll change his mind," she said.

Petersen said she has seen a pattern of disagreements between Kuehn, who's been mayor since 2008 and a council member since 1990, and other council members. She said the mayor has "lashed out before" at at least one colleague, bringing her "to tears."

"Before we can move on, we have to look at this and learn from it," she added.

Thorsen said he's going to stick to his decision, whether the council likes it or not.

"It's my decision to make," he said, adding that he will continue working for the city as a volunteer firefighter.

City Manager Jason Ziemer said the council could act on the resignation at its April 7 meeting. If it accepts the resignation, it will declare the seat vacant and decide in coming months whether to fill it through a special election or by appointment, he said.

Blair Emerson is a University of Minnesota student reporter on assignment for the Star Tribune.