Rome (CNN) -- Technical experts directing the salvage operation aboard the Costa Concordia cruise ship are recommending that the underwater part of the operation be called off because it is becoming too dangerous, Italy's civil protection agency said Tuesday.
The head of the operation, Franco Gabrielli, will make the final decision, but is unlikely to go against the recommendations of the technical experts, his office said.
The advice is based on safety concerns and follows consultations with relatives of the people still missing from the shipwreck and diplomats representing their countries, the civil protection agency said.
A total of 15 people remain missing after the cruise ship's collision with rocks off the coast of Tuscany on January 13. Seventeen bodies have been recovered. There were about 4,200 people on the cruise liner when it crashed.
Franco Schettino, captain of the Costa Concordia, said that after the ship hit the rocks, he ran it aground off Giglio island to keep it from sinking and limit the tilting. It came to rest on its starboard, or right, side, with roughly 50% of the ship under water. It is currently rotated nearly 90 degrees.
Salvage operations in the part of the ship above the water line will continue, Gabrielli's office said, as will searches of 7 square miles (18 square kilometers) of sea around the wreck.
Underwater operations have previously been temporarily suspended for safety reasons, but have always resumed. Technical experts are now advising that they come to a permanent end.
Schettino is under house arrest on suspicion of manslaughter, causing a shipwreck and abandoning ship while passengers were still on board.
He denies the charges, saying his actions saved lives.
Schettino has admitted to prosecutors, defense attorneys and a judge that he made a "mistake" in colliding with the rocks off shore. But he has brushed aside suggestions that he was going too fast, as prosecutors allege.
The lead prosecutor in the case is asking that Schettino be sent back to jail. A hearing has been scheduled for February 6.
But Schettino's lawyer says he should be released from house arrest.
Officials are particularly concerned for divers who are searching submerged areas of the ship amid a sea of debris that includes heavy items and wires, they said Sunday.
The ship jolted slightly and then slowly moved even further, totaling about 4 centimeters over a few hours, Gabrielli said Sunday.
The ship's movement renewed fears that the vessel could slide farther.
Earthquakes in the region last week also stoked fears that the ship could plunge deeper into the water.
Gabrielli said that if the ship does not slip into deeper water, it will take at least seven to 10 months to remove the wreckage. And that process won't begin until after the fuel is removed, which could take 28 working days once it begins.
In the meantime, there will be no fishing, diving, snorkeling, or other normal use of the water near the wreckage, extending the disaster's economic toll.
A number of survivors have filed lawsuits against the company that ran the cruise, Costa Cruises.
Costa has announced it was offering each of about 3,200 passengers who had been aboard the vessel a lump sum of 11,000 euros ($14,400), in compensation for their loss of property and emotional distress, as well as a refund of costs associated with the cruise.
Separate agreements will be reached with those passengers who were injured and needed treatment at the scene and with the families of those who died, Costa said.