New York has reached a deal with its teachers union, ending a five-year stalemate, Mayor Bill de Blasio announced on Thursday.

The New York Times reports de Blasio, a liberal Democrat taking on a tough issue during his first year in office, called it a "landmark" labor deal. The Times adds:

"The deal, hammered out in marathon negotiations this week, will grant $3.4 billion of back pay to the union, the United Federation of Teachers, in exchange for a substantial reduction in health care costs and an easing of classroom work rules that have long frustrated city officials. Teachers will also receive raises totaling 10 percent over seven years."The agreement, which must be ratified by the union's 100,000 members, is a milestone moment for Mr. de Blasio, a Democrat with longstanding ties to the city's labor groups. And it is a stark break from the tone set by his predecessor, Michael R. Bloomberg, who had promoted pay freezes and other stringent tactics in an era when many cities are cutting back on wages and benefits for their labor force."

The AP reports the deal could become a template for other contracts, because nearly 150 other city labor unions have been working with expired contracts.

The teachers union represents 100,000 teachers who teach in a system serving 1.1 million students. The system is by far the largest in the country.

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