The overall project is expected to generate 6,000 construction-related jobs and double train capacity into and out of Manhattan.
The decision comes amid concern from federal officials that the project may go as much as a billion dollars over budget _ money New Jersey doesn't have.
James Weinstein, New Jersey Transit's executive director, told The Star-Ledger of Newark that the monthlong suspension of all new activity will be used to re-examine the budget numbers. He also hopes to use the time to prove to all parties involved that the project's $8.7 billion cost estimate is accurate.
Work already under way on the tunnel, including a track underpass in North Bergen and a tunnel segment under the Palisades, will be allowed to continue during the suspension.