Thirty massive tanks filled with air will lift the hulk of the Costa Concordia off the seabed in June so it can be towed away from the Italian island of Giglio where it capsized two years ago.
The 114,500-ton vessel hit rocks on January 13, 2012, killing 32 people. It was hauled upright in a complex "parbuckling" operation in September but still rests where it capsized, just outside the holiday island's small port.
The ship's captain Francesco Schettino is on trial for manslaughter, causing the wreck and abandoning ship. He says he was not the only person to blame for the disaster.
Refloating the Concordia will be one more phase in the largest maritime salvage operation in history. Where the ship will be dismantled – the final step – has yet to be decided.
"This incident is part of our DNA and our mission is to make sure that it never happens again," Michael Thamm, chief executive of Costa Crociere, a unit of Carnival Corp, which owns the liner, said.
"We are very confident we can remove the ship from the island within the month of June."
The Concordia salvage is expected to be the most expensive wreck recovery ever, costing more than €600m, more than half the overall insurance loss of more than €800m.
Around two and a half times the size of Titanic, the Costa Concordia was typical of the latest generation of cruise liners, built to carry thousands of passengers and keep them entertained with restaurants, cinemas and bars.