BOGOTA (REUTERS) - Colombian naval officials conducting underwater monitoring of the long-sunken San Jose galleon have discovered two other historical shipwrecks nearby, President Ivan Duque said on Monday (June 6).

The San Jose galleon, thought by historians to be carrying treasure that would be worth billions of dollars, sank in 1708 near Colombia's Caribbean port of Cartagena.

Its potential recovery has been the subject of decades of litigation.

A remotely operated vehicle reached 900 metres depth, Duque and naval officials said in a video statement, allowing new videos of the wreckage.

The vehicle also discovered two other nearby wrecks - a colonial boat and a schooner thought to be from around the same period as Colombia's war for independence from Spain, some 200 years ago.

"We now have two other discoveries in the same area, that show other options for archaeological exploration," navy commander Admiral Gabriel Perez said. "So the work is just beginning."

The images offer the best-yet view of the treasure that was aboard the San Jose - including gold ingots and coins, cannons made in Seville in 1655 and an intact Chinese dinner service.

Archaeologists from the navy and government are working to determine the origin of the plates based on inscriptions, the officials said.

"The idea is to recover it and to have sustainable financing mechanisms for future extractions," President Ivan Duque said. "In this way we protect the treasure, the patrimony of the San Jose galleon."