Marine archaeologists believe they have finally identified the resting place of HMS Endeavour, the ship James Cook commanded to New Zealand on his first voyage of discovery, an achievement that would solve one of the greatest maritime mysteries of all time.

The breakthrough has raised hopes the vessel will be excavated next year, in time for the 250th anniversary of Cook's arrival in Australia. The ship is historically significant to many countries - including the US, Britain, New Zealand and Australia - and its excavation could spark a battle over where the wreckage should be housed.

The breakthrough, to be officially announced on Friday, follows an arduous 25-year search for the historic ship off Newport, Rhode Island, on the north-eastern coast of the US.

SUPPLIED A painting of HMS Endeavour, which researchers believe they have discovered off the coast of the United States.

Archaeologists from the Australian National Maritime Museum and the Rhode Island Marine Archaeology Project will release a detailed 3D image of the site in Newport Harbour where they believe the ship is located.

Peter Dexter, the chairman of the Australian National Maritime Museum, is travelling to the United States to attend the event, as will Australia's consul-general in New York, Alastair Walton.

Supplied Captain Cook, who brought the British Empire to the Pacific sailing the Endeavour.

Over 25 years, marine archaeologists have narrowed down the search for the Endeavour from a fleet of 13 vessels to five, and have now pinpointed one extremely promising site.

The site is located just off Goat Island, a small island in the Narragansett Bay.

Dr Kathy Abbass, director of the Rhode Island Marine Archaeology Project, said: "We can say we think we know which one it is.

ROBERT PEARCE/SYDNEY MORNING HERALD The Endeavour replica heads up the coast off Sydney in 2005.

"It is exciting, we are closing in.

"This is a vessel that is significant to people around the world."

Abbass said she was hopeful the ship could be excavated next year, in time for the April 2020 celebrations marking 250 years since Cook's arrival at Botany Bay.

She said the identity of the ship will only be definitively proven after its excavation, which will require significant funding.

The Endeavour was purchased by the British Navy in 1768 for a scientific mission to the Pacific Ocean and to locate the mysterious southern continent then known as Terra Australis.

Cook departed Plymouth in August 1768, travelling through the Pacific Islands before arriving in New Zealand in September 1769.

In April 1770, Endeavour became the first ship to reach the east coast of Australia, when Cook arrived at the site now known as Botany Bay.

The ship was sold in 1775 and renamed Lord Sandwich 2. It was hired as a British troop transport during the American War of Independence and was scuttled in a blockade off Rhode Island in 1778.

Volunteer researchers from the Rhode Island Marine Archaeology Project began their study of the group of vessels believed to include the ship in 1993.

In recent years, the Australian National Maritime Museum has provided grants to help fund the deep-dive and remote sensing studies that have helped narrow the search for the ship.

"Now that RIMAP [Rhode Island Marine Archaeology Project] and the ANMM [Australian National Maritime Museum] have identified a possible site in Newport Harbor that might be the Lord Sandwich ex Endeavour, the detailed work must begin to prove it," Abbass said in a statement posted on the group's website on Tuesday (US time).

"Therefore, fundraising is ongoing for the artifact management facility needed to process, store, and display the artifacts that will emerge from the planned 2019 excavation."