Conservative MP Scott Aitchison is resigning his seat from Parliament by the end of the year – according to a source close to him – and is set to become the eighth person to leave Pierre Poilievre’s caucus in less than a year.

The source tells CTV News that after being in elected office for 30 years, Aitchison will be stepping back to pursue other opportunities. A formal announcement is expected in the coming days.

CTV News has also learned that Aitchison informed Poilievre about his decision to resign last week.

Speculation about Aitchison’s departure was first reported by The Hill Times on Tuesday.

Aitchison has represented the riding of Parry Sound-Muskoka as an MP since 2019, and previously ran for the Conservative leadership in 2022, where he lost out to Poilievre. Prior to his time in federal politics, he served as the mayor of Huntsville from 2014 to 2019.

Aitchison’s sudden decision to resign comes as Poilievre faces internal leadership questions, as reported by CTV News in August.

Poilievre has also lost seven other MPs since last fall. Chris d’Entremont, Michael Ma, Matt Jeneroux and Marilyn Gladu all crossed the floor to the Liberals over the course of several months, while Richard Martel left for a Senate appointment. Larry Brock and Cathay Wagantall, meanwhile, have recently left federal politics, leaving their seats vacant.

The Conservatives also continue to lag in the polls, with the most recent Nanos Research numbers putting the Liberals at 49.9 per cent support and the Conservatives at 27.9 per cent. The same poll also shows 61.5 per cent of Canadians support Mark Carney as preferred prime minister over Poilievre, who sits at 19.6 per cent.