Jersey City Mayor Steven Fulop axed an aide because the staffer refused to disavow his Republican sister during her controversial run for political office, the lefty Democrat said this week.

Jonathan Gomez-Noriega sister is firebrand conservative Valentina Gomez, who sparked controversy on the run up to her failed bid Tuesday to become the GOP nominee for Missouri’s secretary of state, cursing in some campaign ads and in others, encouraging Americans not to be “weak and gay.”

In one anti-woke spot, she used a flamethrower to burn a pile of sexually suggestive LGBTQ+-themed books she said indoctrinated children.

When Fulop learned Gomez-Noriega, an aide for six years, contributed an unspecified amount to his sister’s MAGA campaign, he demanded he renounce her online — and even directed Gomez-Noriega on what to say.

“I love her as a sister but I don’t condone her actions that have become progressively more vile over the last few months,” Fulop suggested Gomez-Noriega write, according to text messages the mayor shared on X.

But Gomez-Noriega refused, saying he was intent on supporting his sister.

The final straw for Fulop came when Gomez-Noriega traveled to Missouri Monday to campaign for his sister.

Gomez-Noriega was fired on Wednesday, because the primary aide position entailed “dealing with a lot of the diversity issues around Jersey City,” the mayor said. “He can no longer fulfill that job because of lack of trust.”

Gomez, a real estate investor, who finished a distant sixth in Tuesday’s race, ripped the move as “straight out of Nazi Germany.”

“This proves that Democrats think you should be unemployed if you don’t denounce your family members,” Gomez told The Post, adding the family is planning to sue the mayor and the city.

Gomez-Noriega could not be reached for comment.

A Garden State GOP operative likened the firing “to the great purge in Mao’s China.”

“Fulop made a very political calculation with this, that he’s going to trade taxpayer dollars — because he knows this is going to become a lawsuit — for political capital in his race for governor,” the GOP operative said.

He’s willing “to show that he’s this progressive warrior that will stop at nothing to rid the world of MAGA and anything affiliated with it — even siblings,” the operative added.