Firebrand progressive Rep. Alexandria Ocasio-Cortez has escalated her feud with fellow New York congress member Sean Patrick Maloney — officially backing a primary challenge by left-leaning state Sen. Alessandra Biaggi ahead of the Aug. 23 Democratic primary. 

“We can count on her to stand with our movement on critical issues such as abortion rights, championing the Green New Deal and Medicare for All,” Ocasio-Cortez said in a press release. 

The Biaggi endorsement follows tensions between Maloney, AOC and other progressives after he announced plans to run in a newly-drawn district covering parts of Westchester, Rockland and Putnam counties that had been represented by Ocasio-Cortez-aligned Rep. Mondaire Jones.

“We are going to have to agree to disagree. This election comes down to voters in NY-17 and I am honored to have received overwhelming support locally, including endorsements from nearly 40 elected leaders and Democratic Party committees,” Rep. Maloney (D-Westchester) said in a statement Tuesday.  

The ongoing friction between AOC and Maloney is part of a wider civil war sparked by the new congressional lines. 

Biaggi launched her primary challenge after Jones (D-White Plains) decided to run for the newly redrawn 10th district seat running from Park Slope, Brooklyn to Lower Manhattan that has been vacated by veteran Rep. Jerrold Nalder.

Progressives had accused Maloney, a gay, white man, of leveraging his powerful role as Democratic Congressional Campaign Committee over Jones – among the few gay, black men in Congress – after he announced plans to run for the left-leaning district. 

Ocasio-Cortez has called for Maloney to resign the chairmanship of the committee, which aims to help party incumbents win reelection, for going after Jones’ seat. 

“I don’t think he should be DCCC chair if he’s going to challenge another member. It’s completely inappropriate,” Ocasio-Cortez said last month. 

The inter-party strife flared up after court-appointed special master Jonathan Cervas released a new congressional map once the courts tossed a so-called “Hochulmander” backed by congressional Dems.

AOC and Maloney are hardly the only Democrats fighting following the implosion of the gerrymandering effort that might’ve helped the Democrats flip several GOP-held seats across the state.

Rep. Carolyn Maloney (D-Upper East Side) and Rep. Jerrold Nadler (D-Upper West Side) are battling it out in Manhattan over who gets to represent turf that overlaps with both of their current districts. 

Things have already gotten heated between the two longtime reps, with Maloney recently accusing Nadler of sexism for not stepping aside. 

Big name Democrats like former Mayor Bill de Blasio and Assemblywoman Yuh-Line Niou (D-Manhattan) are also running against Jones in the primary.

“In a year where we have major battles to fight, including protecting Democratic majorities, the internecine warfare among Democrats is astounding,” political consultant Jake Dilemani said in a text when asked his take on the AOC endorsement of Biaggi. 

Democrats are defending a slim majority in the House of Representatives this year in the face of political winds that appear favorable to the GOP. 

AOC rose to fame by beating longtime incumbent Rep. Joe Crowley (D-Queens) in 2018 despite his enormous advantage with fundraising and endorsements from major officials.

Biaggi won election to the state Senate that same year by defeating one-time legislative powerbroker Jeff Klein, who had led a band of renegade Democrats that helped the GOP hold the state Senate for years.

“In 2018 when I stood up to the establishment, Rep. Alexandria Ocasio-Cortez’s support helped me win against all odds … we want a champion in Congress that will fight for all of us — not a corporate Democrat like Sean Patrick Maloney who puts his donors interests ahead of ours,” Biaggi said in a press release Tuesday.