He said giant tanks that will help float the ship will be fixed to its side by April, mirroring the ones already welded to the other side before the 290-metre (951-foot) ship was dragged upright in September.
"This would allow us to re-float the ship by June," Franco Porcellacchia told local residents on Giglio, Italian media reported, although he emphasised that it would be "a delicate and weather-sensitive operation".
"I am extremely confident," Porcellacchia said.
He said the ship could then be towed to a nearby port, or part of the way there and then carried by the semi-submersible Vanguard heavy lift ship, which is usually used to transport offshore rigs.
There is still no agreement over what port the Costa Concordia could be taken to for the lucrative scrapping operation, and the most frequently mentioned option, nearby Piombino, cannot take in such a large ship.
The Costa Concordia crashed into Giglio on the night of January 13, 2012 as it was attempting a risky salute manoeuvre close to some rocks just off the
The ship keeled over with 4,229 people from 70 countries on board, and hundreds were forced to jump into the sea during a panicky evacuation.
Thirty-two people lost their lives in the disaster.
The salvage operation for the Costa Concordia, which belongs to cruise ship operator Costa Crociere, is the biggest ever attempted for a passenger ship.