Former President Donald Trump slammed the city Board of Elections on Wednesday after the agency stupendously botched the mayoral primary vote count in its first-ever ranked-choice race.

In a statement, the 45th commander-in-chief lamented the alarming errors by the agency, which failed to notice that 135,000 pre-election “test” ballots had been added to the count.

“It was announced overnight in New York City that vast irregularities and mistakes were made and that Eric Adams, despite an almost insurmountable lead, may not win the race,” Trump said, referencing the Democratic primary front-runner.

“The fact is, based on what has happened, nobody will ever know who really won,” he continued.

“Watch the mess you are about to see in New York City, it will go on forever. They should close the books and do it all over again, the old-fashioned way, when we had results that were accurate and meaningful.”

The Democratic primary race for mayor was thrown into chaos Tuesday after the ballots, which hadn’t been cleared from a computer, were noticed by Adams’ campaign.

Preliminary results released earlier in the day showed a total of 941,832 ballots cast for mayor, an increase of more than 140,000 from the 799,827 that were counted on June 22, the day of the primary.

According to a BOE statement Tuesday night, “it has determined that ballot images used for testing were not cleared from the Election Management System.

“The Board apologizes for the error and has taken immediate measures to ensure the most accurate up to date results are reported.”

In response, the embattled agency scrubbed all the results from its website, replacing them with a message saying, “Unofficial Rank Choice ­Results Starting on June 30.”

Some questioned why the agency even released preliminary results.