PHILADELPHIA -- A nonprofit group that owns the historic 990-foot-long ocean liner that has been moored in Philadelphia for nearly 20 years said on Thursday that the ship has an "exciting future."

The SS United States Conservancy said in a media advisory that it has signed an option agreement with a "major redevelopment partner" whose name was not disclosed. Tom Basile, a spokesman for the conservancy group, said he could not release any other information about the deal.

The group plans to announces further details about the fate of the ship, which was once thought to be headed to the scrap heap, at a news conference in New York City next week.

During that news conference, "an exciting future for the ship will be revealed that envisions the SS United States again as an iconic symbol of America the world over," the group said in a statement.

The ship designed by William Francis Gibbs made its maiden voyage in 1952 and broke the trans-Atlantic speed record, which it still holds today. Four U.S. Presidents sailed aboard the ship, according to the conservancy group, as well as Marlon Brando, Salvador Dali and Grace Kelly, among other famous passengers.

The ship was retired from active service in 1969 and has been moored in South Philadelphia since 1996.

The SS United States glides down the Hudson River as it begins its first voyage to Europe from New York on July 3, 1952.(Photo by Jack Harris | Associated Press)

The conservancy group said in 2014 that they were facing a difficult financial situation as they worked with potential developers and investors to find a way to "repurpose the ship as a museum and mixed-use destination." Maintenance for the ship was costing supporters roughly $60,000 a month.

But restoration efforts continued thanks to some $600,000 in donations the group received last year.

The conservancy's executive director, Susan Gibbs, and the head of the undisclosed development partner will provide more details about the ship's future at a press conference at the Manhattan Cruise Terminal next Thursday.

Erin O'Neill may be reached at eoneill@njadvancemedia.com. Follow her on Twitter @LedgerErin. Find NJ.com on Facebook.