New York City is dialing up its negative rhetoric about Altice NV’s planned purchase of Cablevision Systems Corp.

The city spelled out its specific complaints in a Friday filing with the state’s regulator the New York Public Service Commission, saying it has “serious concern” about the $10 billion deal and that it raises “key public interest questions.” While the filing details its concerns, New York City won’t make a formal decision on the deal until early spring, one city official said.

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