Costa Concordia's Captain Francesco Schettino drank a bottle of wine accompanied by a mysterious Moldovan dancer and a high official of the liner before the shipwreck, a witness has reported.

Passanger Angelo Fabbri, who also took the picture that allegedly shows the woman, Domnica Cemortan, dining at the luxury Club Costa restaurant, claimed Schettino remained seated until 9.05pm - less than 40 minutes before the ship hit rocks off the coast of Giglio island.

"There is no doubt they were drinking, at least, a whole decanter," Fabbri told daily Il Secolo XIX and La Repubblica. "They laughed a lot and there seemed to be a lot of intimacy between the three. The last drops were poured in the captain's glass."

After dinner, Schettino and his guests reportedly went to the bridge deck where the captain committed the bravado challenge that led the ship to hit the rocks.

Italian prosecutors have been trying to trace his blonde companion, who reportedly works for the Costa Crociera Company - the ship's owners - but was on holiday when she boarded. She is believed to have worked as a dancer on another cruise ship in 2007.

Costa Concordia: Mystery of Blonde Moldovan Woman Domnica Cemortan [SLIDESHOW]

Reports suggest that the woman was not assigned a cabin.

Cemortan gave a brief interview to the Moldovan channel Jurnal TV, in which she defended Schettino against allegations that he abandoned the ship after it hit rocks.

"He saved thousands of lives," she said. "I think he did an extraordinary job and all the crew is supporting him and think he saved more than 3,000 lives."

In another interview with the website, she said she was having dinner when the accident occurred.

"I climbed to the main deck and started translating in Russian information given by officials," she said. "I left the liner at 11.50pm and the captain was still on board. He helped evacuate people from the ship."

The Italian daily La Stampa reported that another passenger, of British nationality, had spotted Cemortan drinking with Schettino before the crash.

Investigators want to establish exactly where she was at the time of the accident off the Tuscan coast, when the captain was apparently making a salute to an old friend.

The cruise line has suspended Schettino, who remains under house arrest while facing charges including manslaughter and abandoning the ship.