Mayor Bill de Blasio ripped an MTA workers' union ad published in newspapers yesterday as "specious" and "inaccurate."

The ad, created by the Transport Workers Union Local 100, showed the mayor jumping a turnstile -- and said the city would be to blame if the subway system deteriorated to the days of the '70s. The ad ran in amNewYork and the Daily News.

"I'm going to leave you to do a little bit of simple research about why the transit workers union would so conveniently [be]attacking us and who they respond to," said de Blasio, alluding to the governor."But the bottom line here is it is...an unfair argument."De Blasio and Cuomo have clashed throughout the mayor's term -- with the latest saga taking place over funding for the MTA's $26.8 billion capital plan, which has to be approved soon by a review board. The MTA is a state authority.

The governor has asked the city to pay $3.2 billion of the plan -- following the MTA's original request of$657 million. De Blasio said the city already gives the MTA enough money, and that the state has raided transit dollars in the past.

"We want greater transparency and accountability," he said. "That's the big picture situation with the MTA."

MTA spokesman Adam Lisberg said the city needs to pay more because it represents 90% of the MTA's customers, and 80% of its transit network. "Once again, the city is going in circles, using cheap excuses to avoid investing in the mass transit network that makes New York possible," he said.

John Samuelsen, who heads TWU Local 100, also pushed back at de Blasio yesterday Monday. He slammed an article that ran in the New York Observer yesterday Monday. Anonymous labor officials in the piece said Samuelsen was "doing Gov. Andrew Cuomo's dirty work" in his City Hall feud.

"The mayor should stop using anonymous surrogates to attack those who tell the truth about New York City's gross shortchanging of our transit system," Samuelsen said in a statement. "By not paying his fair share, Mayor de Blasio is doing real harm to the working families who rely on our great system."