Brooklyn federal Judge Jack Weinstein said Tuesday he would set a date for a special election to fill the seat of former Staten Island Rep. Michael Grimm if Cuomo doesn’t do it by noon Friday.

“Unless the governor announces a date for a special election on or before noon on Friday, Feb. 20, 2015, or justifies a further delay . . . at that time and date, this court will fix the date . . .” said Weinstein. “Unjustified delay in filling a vacancy cannot be countenanced.”

Weinstein ruled on a suit brought by political activists upset that Cuomo still hasn’t called an election to replace Grimm who resigned Jan. 5 after pleading guilty to tax evasion.

Plaintiffs’ attorney Ronald Castorina Jr. said the decision could set a precedent: “It is extremely rare for a federal judge to compel the governor to take action.”

Cuomo spokeswoman Melissa DeRosa said the governor would announce the election date “shortly.”