MONTREAL -- A witness at Quebec's corruption inquiry is rejecting earlier testimony that led to the resignation of former Montreal mayor Gerald Tremblay.

Marc Deschamps says testimony from a former party organizer that Tremblay knew about two sets of financial books during a 2004 meeting was not true.

The claim last fall was politically devastating to the mayor and he resigned soon thereafter -- a year before a scheduled election.

Deschamps' testimony Monday set the table for a trio of high-profile witnesses coming up at the inquiry over the coming days: former Union Montreal party fundraiser Bernard Trepanier; former executive committee head Frank Zampino; and the ex-mayor, Tremblay.

As for that infamous meeting, where Tremblay was supposedly made aware of the crooked book-keeping, Deschamps was matter-of-fact.

"That meeting never took place," said Deschamps, a former official agent for Union Montreal, the municipal party that was in power until last year.

An earlier witness had suggested Deschamps revealed crooked financing practices to the mayor at a meeting nine years ago.

This is not the first time that testimony of Martin Dumont has been challenged. Dumont, who made the claims about the mayor, has admitted he made up an anecdote during another part of his testimony.

Deschamps talked Monday about having to fire the man now nicknamed dubbed "Mr. Three Per Cent." Deschamps says it was done in February 2006 on the orders of then-mayor Tremblay.

Trepanier was making $82,000 a year as director of financing and he didn't leave empty-handed -- Trepanier walked away with four months of salary continuance and $25,000 in severance pay.

Still, Trepanier continued to work for the party for three years after that, maintaining paperwork that identified him as a recognized fundraiser for the party until 2009.

Inquiry counsel Paul Crepeau suggested a reason for Trepanier's departure: that the mayor had caught wind of a rumour that Trepanier had tried to extort $1 million from a shopping-centre promoter.

Deschamps, who was the party's official agent, said he'd never heard of the allegation.

He also said he'd never heard of another bombshell suggestion from Crepeau: that Trepanier walked out of Union Montreal offices with shoe boxes filled with $100 bills after he was fired.

Deschamps, speaking in a slow, quiet tone, said he only found out in 2012 during a conversation with Tremblay why Trepanier was let go.

Tremblay apparently had a problem with Trepanier's "proximity" to Zampino. No other reason was ever revealed to Deschamps.

"He was asked to leave," said Marc Deschamps. "I do not know the exact words that were used."

Deschamps' evasive answers about Trepanier's departure led to a testy exchange.

"Don't play dumb -- there's a reason," commission chair France Charbonneau told the witness. Deschamps replied that he wasn't aware.

Trepanier stood out from other fundraisers. He was the most successful bagman in the party's history, Deschamps said.

Deschamps said he never asked why that was the case.

And he rebuffed an assertion from commissioner Renaud Lachance that it was Deschamps' responsibility to make sure Trepanier was playing within the rules.

Deschamps said it wasn't his job to make sure everything was legitimate.

"You set the bar too high," Deschamps told Lachance.

Trepanier is expected before the inquiry later this week.