Conservatives in the Senate will be picking a new leader this spring after Claude Carignan told his colleagues Tuesday he plans to leave the post at the end of March.
The decision means the Conservatives will have a new leader in the upper chamber less than two months before party members choose a successor for Rona Ambrose, the party's interim chief in the House of Commons.
In a statement, Carignan says now is the time for the Senate caucus to renew its leadership.
Carignan has served as Tory leader since 2013, when former prime minister Stephen Harper appointed him to replace Sen. Marjory LeBreton who stepped down from the post.
Carignan wasn't made a cabinet minister like his predecessors,but sat on key cabinet committees as the Tories tried to distance themselves from the spending questions surrounding Mike Duffy, Pamela Wallin and Patrick Brazeau.
Shortly after taking up his post, Carignan led the charge in the Senate to suspend all three senators without pay for two years.
Duffy was later acquitted at trial of all criminal wrongdoing, while the RCMP closed files on Wallin and Brazeau without laying any charges.
The affair accelerated the Senate's modernization agenda, which included being more transparent about spending and exploring whether to televise proceedings.
Carignan says the Senate still has more work to do become the modern institution he wanted to see, but adds that senators have made "giant strides" over the past six years.