MONTREAL—With the vote for interim mayor scheduled for Friday, the scene at Montreal’s city council is chaotic as cross-party negotiations, coalition building and intense politicking shatters any sense of party unity.

The governing Union Montreal party had chosen Richard Deschamps as its candidate for the temporary seat, but former executive committee chair Michael Applebaum is overlooking the snub by his party and is aiming for the top job.

“I think that I’m very well placed in the knowledge, stability and ability to run the executive committee and to work with all parties,” said Applebaum, who resigned from the head of the executive committee on Friday.

With defections and resignations, Union Montreal now only has a slight majority in council, holding 33 out of 63 seats—that number includes Applebaum, who is not even certain he will remain a member of former mayor Gerald Tremblay's party.

"For myself as a member of Union Montreal I can tell you also I am in serious reflection and I will be looking at that over the next hours and the next days on exactly where I stand with Union Montreal," said Applebaum.

Applebaum is actively courting the four independent councillors, as well as members of Vision Montreal and Projet Montreal, to support his bid to become interim mayor.

“I’ll be sitting down with Madame Harel, with Richard Bergeron, discussing a coalition and how they see the city going forward from Friday on,” said Applebaum, referring to the opposition leaders.

"There has to be a coalition of all of the different political parties and the interim mayor has to be someone who is independent and who is also not going to present themselves as mayor for 2013.”

He says he's called Deschamps but hasn't heard back yet. Speaking to reporters on Monday, Union Montreal’s heir apparent said he wasn’t happy with Applebaum, but was willing to talk.

“The way he has acted has surprised me very much,” said Deschamps. “I think it's questionable.”

Applebaum says he left the executive committee because it refused to re-evaluate planned tax hikes in the wake of Tremblay's resignation. In a bombshell, he also said that the committee did not want to release a recently-discovered 2004 report into construction cost overruns.

Other members of Union Montreal said Applebaum is just angry because he did not win the support of enough councillors to be the party’s candidate for interim mayor.

Vision Montreal leader Louise Harel met with both Deschamps and Applebaum this afternoon, but isn't saying who her party is leaning towards.

“The most important thing is to be sure the cleanup will happen at city hall,” said Harel.

The members of the city’s second opposition, Projet Montreal, say they are working towards a coalition.

Backroom negotiations are expected to continue for days.