NEWARK - A new study announced yesterday says a $9 billion rail tunnel would cut down on the commuting time between New Jersey and New York City.

U.S. Sen. Frank Lautenberg says the average commuter would save 15 to 30 minutes a day if a new tunnel under the Hudson River is built. It would start in North Bergen and end at West 34th Street in New York City.

The Democrat announced the results of the Regional Plan Association study at Newark's Penn Station yesterday.

Republican Gov. Chris Christie shelved the project because of cost overruns. But he gave it a two-week reprieve after meeting with U.S. Transportation Secretary Ray LaHood on Friday.

Lautenberg didn't say whether a federal or state agency might be asked to pay for overruns. He said he has spoken with an unnamed financial firm about possible private funding to keep the project on track.

AP wire services contributed to this report.