A high-profile Liberal MP won't be running in this fall's federal election.

Andrew Leslie, a retired lieutenant-general who was elected in 2015, is stepping away from politics after one term as an MP.

"I believe it is time for me to take a new path," Leslie wrote in a letter posted on his website.

Leslie, 61, served as chief government whip when the Liberals took office and was later appointed as parliamentary secretary to the minister of foreign affairs. He represents the eastern Ontario riding of Orléans.

Before entering politics, Leslie served in the Canadian Armed Forces for 35 years. (Bill Graveland/Canadian Press)

Leslie will step down from his parliamentary secretary role but will remain on as an MP until the writ is dropped.

Leslie took on "special responsibilities" as parliamentary secretary, focusing on the Canada-U.S. relations file. He held the position during the NAFTA negotiations last year involving Foreign Affairs Minister Chrystia Freeland.

In his letter, he thanks Prime Minister Justin Trudeau for appointing him to the role and praised some of the Liberal government's work, specifically on infrastructure and defence spending.

Leslie also touts the money the Liberals have spent in the last three budgets to support veterans, but adds he hopes more will come.

Liberals losing incumbents

Leslie's announcement comes as the Liberals have been slipping in the polls, and follows other party incumbents who have said they won't be running for the October election. They include:

Longtime Nova Scotia MP Rodger Cuzner, who announced last week he won't be seeking re-election. Cuzner served as parliamentary secretary to former prime minister Jean Chrétien in 2003. He also served as chair of the Nova Scotia caucus and party whip.

Cuzner's longtime friend and colleague, Sydney-Victoria MP Mark Eyking, who made the announcement in February.

Scott Brison, another longtime Nova Scotia MP and former Liberal cabinet minister, said in January he would be stepping away from politics. He stepped down as an MP in February.

Ontario MPs Borys Wrzesnewskyj and Kyle Peterson.

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