The former agriculture minister and MP for a Saskatchewan riding will make the announcement Thursday, Global News’ David Akin confirmed.
Ritz was first elected in 1997 as a member of the Reform Party, and went on to win his seat in every subsequent federal election.
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Between 2007 and 2015, he served as agriculture minister under former prime minister Stephen Harper, overseeing among other things the marquee Conservative promise to overhaul the Canadian Wheat Board.
In 2008, in the midst of an outbreak of listeriosis that killed about 20 people, he drew widespread condemnation for cracking a joke that the political damage from the issue was “like a death by a thousand cuts. Or should I say cold cuts.”
He later apologized for the remark, which Harper’s office had called tasteless and completely inappropriate.
Ritz had informed Scheer of his planned retirement earlier this summer as the Conservative leader was in the midst of putting together his shadow cabinet.
Under interim party leader Rona Ambrose, Ritz had served as critic for international trade. That position will now be held by Ontario MP Dean Allison.
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Ritz, 66, had spent two decades working as a farmer before entering political life. He won office in the same election that saw Deepak Obhrai secure a seat for the Reform Party in Calgary – Obhrai was sworn in before Ritz, because of the alphabetical list, so is technically considered the longest serving Tory MP.
But the duo represent the last of the old Reform guard in the House of Commons.
Just after the Tories were reduced to Opposition status last election, Ritz told the Manitoba Cooperator his wife had hoped he wouldn’t run again in the 2015 race, but he felt had unfinished business.
“I’m not ashamed of anything I have done or how I’ve done it,” he said.
“I certainly will look anybody in the eye and say ‘the greater good prevailed’ and that’s what democracy is all about – having your say but not having your way (necessarily) with the election we just went through.”