Costa Cruises said its president, Gianni Onorato, has resigned to pursue other interests. No successor was immediately named.
Two sources with knowledge of the situation told Travel Weekly that Onorato was resigning to take a position with MSC Cruises.
The sources, who asked not to be identified because they were not authorized to speak officially, said they did not know what position Onorato would be taking with MSC, a privately-held, family-owned, Italian cruise line with a fleet of 12 ships.
Rick Sasso, president of MSC Cruises USA, said he couldn't comment on "rumors" that Onorato would be joining MSC.
"He's Italian, so it natural that people would think like that," Sasso said.
Onorato’s departure is effective immediately said Michael Thamm, CEO of Costa Crociere.
"I regret Gianni's decision," Thamm said. "He has played an important role in the development and growth of Costa Crociere."
Onorato had been president since April 2004, and helped direct the company's response to the 2012 Costa Concordia grounding.
He had previously been vice president of cruise operations.
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This report was updated on Tuesday evening to add that sources said Onorato will work for MSC Cruises.