The owner of New York City's World Trade Center has approved incentives for the building where 21st Century Fox and News Corp. are considering leases.

The Port Authority of New York and New Jersey announced Thursday approval of changes in a lease agreement for 2 World Trade Center.

Twenty-First Century Fox and News Corp. are considering renting about 1.5 million square feet. The agency says the deal will move forward with a $19 million contribution from the developer Silverstein Properties and $9 million from the authority.

The Port Authority also said it expects to make at least $500 million in new funds from the deal, which would be used for transportation projects. Executive Director Patrick Foye called the approval of the incentives a "compelling opportunity for the Port Authority."

Foye said the agency is not paying anything but is agreeing to defer $9 million in future ground rents if 2 World Trade Center is built.

The authority oversees the region's airports, bridges and tunnels and owns the trade center site.

Silverstein and 21st Century Fox did not immediately respond to messages seeking comment. A representative from News Corp. declined to comment.

The concessions mark a shift from earlier declarations that there would be no public sector support for the building.

The agency said the proposed public support totals about $16 per square foot for Tower 2, spread over a 30-year initial lease term. That's below the support given for tenants in 1 World Trade Center and Tower 3, which ranged as high as $250 per square foot, the agency said.