The captain of the Italian cruise ship which ran aground late on Friday appears to have taken the vessel very close to the shore in a dangerous manner, officials said on Saturday.

At least three people died in the disaster. The huge, 290 metre long vessel, carrying more than 4,200 passengers and crew, ran aground in shallow waters off the Tuscan island of Giglio but the exact circumstances of the incident remain unclear.

"There was a dangerous close approach which very probably caused the accident, although it will be for the investigation to establish that fully," coast guard spokesman Luciano Nicastro told SkyTG24.

He said the captain then attempted a safety manoeuvre, setting anchor and bringing the ship closer to the shore to facilitate a rescue.

"This was an operation which allowed thousands of people to be taken ashore quickly and in a reasonably safe manner," he said.

The ANSA news agency quoted the state prosecutor of the town of Grosetto as saying that the captain brought the ship close to shore "very clumsily".