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WASHINGTON, DC - JANUARY 25:  Sen. Jeff Flake (R-AZ) delivers remarks during the U.S. Conference of Mayors 86th annual Winter Meeting at the Capitol Hilton January 25, 2018 in Washington, DC. Flake spoke during the conference's Childhood Obesity Prevention Awards Luncheon which was sponsored by the American Beverage Association, whose members include producers and bottlers of soft drinks, bottled water, and other non-alcoholic beverages. The non-partisan conference of mayors from cities with populations of 300,000 or larger meet annually in Washington, DC.  (Photo by Chip Somodevilla/Getty Images)
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WASHINGTON, DC - JANUARY 25: Sen. Jeff Flake (R-AZ) delivers remarks during the U.S. Conference of Mayors 86th annual Winter Meeting at the Capitol Hilton January 25, 2018 in Washington, DC. Flake spoke during the conference's Childhood Obesity Prevention Awards Luncheon which was sponsored by the American Beverage Association, whose members include producers and bottlers of soft drinks, bottled water, and other non-alcoholic beverages. The non-partisan conference of mayors from cities with populations of 300,000 or larger meet annually in Washington, DC. (Photo by Chip Somodevilla/Getty Images)
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Story highlights

"I don't rule anything out, but it's not in my plans," Flake said

Flake is a frequent critic of President Donald Trump

CNN —  

Sen. Jeff Flake says he isn’t ruling out a 2020 presidential run following his term in the Senate.

The Arizona Republican, who announced in October he would not be seeking re-election in 2018, told ABC’s “This Week” in an interview that aired Sunday that he doesn’t have any formal plans to run for President following his time on Capitol Hill.

“I don’t rule anything out, but it’s not in my plans,” Flake said.

Flake, a frequent critic of President Donald Trump, announced his decision to retire with a speech on the Senate floor that bemoaned the “coarsening” tenor of politics in the United States, and criticized his own party’s “complicity” with Trump’s behavior.

On “This Week,” Flake was asked if he would consider running as a Republican or an independent.

“Like I said, I haven’t thought that deeply about it,” he said. “But I do believe if the President is running for re-election, if he continues on the path that he’s on, that that’s going to leave a huge swath of voters looking for something else.”

Flake added that he believes Trump is “inviting” challengers from all sides in 2020.

CNN’s Eric Bradner contributed to this report.