Colombia is making progress toward salvaging a Spanish galleon carrying jewels and coins that sank more than 300 years ago, President Juan Manuel Santos said on Wednesday after receiving a proposal from an investor to bring it to the surface.

The ship San Jose, thought by historians to be carrying one of the largest unsalvaged maritime treasures, sank in 1708 near the historical Caribbean port of Cartagena, and its wreckage was located in 2015.

"The discovery of this ship — one of the most important that navigated in our seas during colonial times — begins a new chapter in the cultural and scientific history, not only of Colombia, but of the entire world," Santos said on national television from Cartagena.