Mayor Bill de Blasio was likened to a motorman in charge of a run-down, graffiti-covered train in an advertisement running today by an MTA workers' union -- the latest attack in a clash between the union, the MTA and the city over capital funding.

"Where Are You Taking Us?" reads the Transport Workers Union Local 100 ad in amNY and the Daily News. "Mayor de Blasio Must Switch Tracks Before Disaster Strikes."

The image will also be used on fliers handed out by transit workers at subway stations.

The union, Gov. Andrew Cuomo and the MTA are pushing Mayor Bill de Blasio to fill a $2.5 billion deficit in the capital plan of the state-run authority, which includes money for new subway cars and bringing the LIRR to Grand Central.

"The city has been getting a free ride, and they really need to fork over the dough on behalf of working families," said TWU Local 100 president John Samuelsen.

The de Blasio administration has said the MTA initially asked them to increase their capital plan contribution by $25 million -- to $125 million over five years.

After the city agreed, it says, the MTA then hiked the desired amount to $3.2 billion. The state has agreed to pay $8.3 billion, but hasn't said where it will get the money.

De Blasio spokeswoman Amy Spitalnick said the city wants to see where the state will get its dollars for the MTA, and it wants $270 million returned to the MTA that the administration and transit advocates say that Albany raided. The city wants a greater say in which projects are funded as well.

MTA spokesman Adam Lisberg, citing an analysis by the Independent Budget Office, said that if the dollars the city has contributed each year to its capital plan had just kept up with inflation it would be paying $363 million a year.

He said the city "needs to do the right thing" and fill the deficit in the capital plan, which includes money for next-generation subway cars, expanded countdown clocks, and the Second Avenue Subway extension to East Harlem.

"We believe it is long past due for the city to make a fair contribution to our Capital Program instead of the paltry $657 million they have offered to date," he said.