The vessel went off the radar in the Gabonese territorial waters on August 14.
"It is known that [the missing ship] is a Panama-flagged tanker of the Greek Lotus Shipping company with two Russian nationals among the crew members. Over the past week, the embassy has been in close contact with the Gabonese authorities, armed forces, and the Gabonese Defense Ministry which have taken all possible measures and used all technical means available to search for the ship in the Gabonese waters," Anton Spiridonov, the head of the embassy's consular service said.
"On Monday, the search operation was finished. Neither the ship nor any traces of a man-made catastrophe, wreckage or accident have been found," Spiridonov said.
"We maintain constant contacts with the authorities, continue gathering information and communicate with the relatives of the missing people," Spiridonov said.
According to the diplomat, the company owning the vessel is working with the countries neighboring Gabon, including Angola, Cameroon, Equatorial Guinea, Sao Tome and Principe, which continue to search for the missing ship.