Former New York City mayor turned congressional candidate Bill de Blasio has accused MSNBC of giving rival Dan Goldman free air time and an unfair advantage in the Democratic primary for the 10th District House seat.

Goldman, the chief Democratic lawyer in the House of Representatives during former President Donald Trump’s first impeachment proceeding, has been a paid legal analyst at the left-leaning cable news outlet.

During a recent remote appearance to discuss the congressional hearings on the Jan. 6 Capitol riot, the attorney could be seen with “Dan Goldman for Congress” posters behind him, de Blasio complained in a letter to MSNBC president Rashida Jones.

“Mr. Goldman is officially a candidate for Congress in the newly created 10th Congressional District in New York City. And as a declared candidate for this seat, he has appeared on MSNBC at least four times, sometimes with advertisements for his campaign in the background shot of these media hits,” de Blasio told MSNBC brass in the letter, a copy of which was obtained by The Post.

“While I deeply respect the expertise of Mr. Goldman, these appearances … are not meant to serve as free advertising for his Congressional campaign,” the former mayor griped.

“These appearances provide him with an unfair competitive advantage against the 14 other candidates in the race and could even be construed as an in-kind donation to Mr. Goldman’s campaign,” he continued.

Saying it’s likely impractical to give all 15 candidates equal air time, de Blasio asked the liberal network to “cease Daniel Goldman’s appearances on MSNBC through the duration of this campaign to ensure nothing of value is being provided by MSNBC to Mr. Goldman or his campaign.”

De Blasio said that two other MSNBC legal analysts who ran office — Maya Wiley for mayor last year and Mimi Rocah for Westchester District Attorney — “rightly removed themselves” from appearing on the air while campaigning. Wiley still made appearances on the network, though no longer as a paid contributor.

A spokesperson for MSNBC declined comment, other than to confirm that Goldman’s paid gig as a legal analyst with the network ended before he announced his bid for Congress.

The friendly fire from de Blasio is raising eyebrows in political circles given that he has appeared more than a half dozen times on MSNBC’s “Morning Joe,” going back to the last term of his mayoralty.

De Blasio even announced his candidacy for Congress on “Morning Joe” on May 20, gushing to co-hosts Joe Scarborough and Mika Brzezinski, “I wanted to come here — a place that I cherish — and with you who have been such good friends.”

A rep for Goldman dismissed de Blasio’s complaint as sour grapes.

“Based on Dan’s work leading the impeachment of Donald Trump, it is not surprising that MSNBC has asked him to provide expert analysis on Trump’s authoritarian scheme to abuse his power and undermine our democracy,” said Goldman campaign spokesman Richard Fife.  

“It is not Dan’s fault or MSNBC’s that Bill de Blasio’s views are not equally valued.”

New York’s 10th Congressional district was formerly represented by Rep. Jerrold Nadler. But following court-ordered redistricting, the Upper West Side turf where Nadler resides was cut out of the 10th and folded into the 12th Congressional district on Manhattan’s East Side. Nadler vacated the 10th CD and instead decided to run in the 12th CD, facing-off against another long-term incumbent, Rep. Carolyn Maloney.

Other candidates in the 10th CD besides de Blasio and Goldman include: Rep. Mondaire Jones, who currently represents the 17th CD in the suburbs north of New York City; Brooklyn Assemblywoman Jo Anne Simon,  Lower East Side Councilwoman Carlina Rivera, Lower Manhattan Assemblywoman Yuh-Line Niou, former Congresswoman and Brooklyn District Attorney Elizabeth Holtzman and Army veteran and anti-communist activist Yan Xiong, among others.

Last year, during his campaign for mayor, Guardian Angels founder Curtis Sliwa took a leave of absence from his slot at WABC radio after he and the station faced gripes about favoritism similar to those levied against MSNBC.