WASHINGTON — Rep.-elect Alexandria Ocasio-Cortez (D-NY) hasn’t taken office yet, but she’s already looking to take out fellow Democrat Rep. Hakeem Jeffries (D-NY), according to a report Tuesday.

Ocasio-Cortez, who shocked the political world when she defeated veteran Queens Rep. Joseph Crowley, said last month she’d support challenges to Democrats who are not as left-leaning as their constituents.

Politico reported that she’s recruited an African-American woman to challenge Jeffries in 2020.

A source told the news website that running a primary rival to Jeffries, who represents parts of Brooklyn and Queens, was the “highest priority” for Ocasio-Cortez.

Jeffries was recently elected the No. 5 Democrat in the House and is considered one of the party’s rising stars.

But in his leadership race, a campaign donation from Rep. Barbara Lee (D-Calif.) to Ocasio-Cortez became part of a whispering campaign that was used to attack Lee, a progressive.

“It’s personal of Ocasio,” one source told Politico. “And she’s going to go all out to take him out.”

Democratic aides told The Post that Ocasio-Cortez’s plotting wasn’t sitting well on Capitol Hill.

“Jeffries is widely respected in the delegation and the caucus,” said an aide to one New York Democrat.

“If this is going to be her approach, she’s not going to make many friends.”

And while Lee and Jeffries’ leadership race was between two members of the Congressional Black Caucus, it doesn’t take away from the fact that Jeffries made history with his win, another Democratic aide pointed out.

“Going after the first black Democratic caucus chair before members are even sworn in seems ill advised,” the aide said.

Ocasio-Cortez denounced the Politico story on Twitter.

“My dad had a name for junk articles like this: `Birdcage lining.’” she tweeted.

In a second tweet, she denounced Politico for using unnamed sources.

“For the record, this is the second @politico article about me in a short period of time with *0* named sources to back claims containing false information. Their articles are printed + distributed to **Congressional offices** – w/ no named sources. It’s really unfortunate,” she wrote.