Leaders of upstate and suburban cities are lining up with Gov. Cuomo to defeat Mayor de Blasio’s tax-the-rich plan to finance universal pre-K in New York City.

“I am surprised to hear that Mayor de Blasio is implying that the children of New York City are more important than the children of my city or other cities in New York state,” Newburgh Mayor Judy Kennedy said in a statement issued Thursday.

Yonkers Mayor Mike Spano — like Kennedy a Democrat — agreed that the state should foot the bill for pre-K for every municipality, the plan advocated by Cuomo and opposed by de Blasio.

“Yonkers is near some of the wealthiest areas of the state, but like most localities, we don’t have a reservoir of millionaires to pay for pre-K,” Spano said.

Republican state senators who chair the committees that must approve the tax hike piled on.

“We know Mayor de Blasio has a lot on his plate, but he may be interested in learning a few facts about the rest of the state,” said Senate Education Committee Chairman John Flanagan (R-Suffolk), Finance Committee chief John DeFrancisco (R-Syracuse) and Rochester-area Sen. Joseph Robach in a joint statement.

“All four of the [other] big city school districts, including Rochester Syracuse and Buffalo, are poorer than New York City, and 70 percent of the 471 school districts across the state — serving more than 1.2 million students — are less wealthy than the one he represents.”

The coordinated comments — coming less than a day after Cuomo made the same points — indicate the governor is mounting a fierce counteroffensive to promote his pre-K plan and to sink de Blasio’s in the Legislature.

The mayor’s allies accused Cuomo and the other mayors of advancing a specious argument.

They said allowing New York City to tax the wealthy to fund pre-K would actually free up more state funds for similar programs elsewhere.

“If the goal is to truly serve the maximum number of 4-year-olds, and not merely to chase public-opinion poll numbers, then he [Cuomo] should support the de Blasio plan and invest state dollars in pre-K for the rest of the state,” said Billy Easton, executive director of the labor-backed Alliance for Quality Education.

Phil Walzak, de Blasio’s spokesman, offered a noncombative response to the other mayors.

He said the city had created “the best pre-K program for our children in New York City and we support every mayor’s vision to do the same.”