The publisher of New Jersey's largest newspaper has renewed a threat to close the paper if he can't reach agreements with four production unions by the end of this month.

Publisher Richard Vezza sent a letter Wednesday to Star-Ledger employees saying the paper would close by Dec. 31 if agreements aren't reached by Sept. 27.

The letter says negotiations with the unions representing pressmen, machinists and engravers are on track, but that talks with the mailer's union have stalled.

A spokesman for the mailer's union said that management is asking for concessions completely at the expense of its members.

Vezza says The Ledger is seeking to stem net operating losses that exceeded $19 million in 2012.

Vezza first issued a threat in June to close the paper as last resort.

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