Amazing footage of a 19-year-old man swimming to stay alive after jumping from Deck 10 of  the Carnival Fascination has emerged on social media.

It is claimed the man, reportedly on his honeymoon, deliberately jumped.

He swam for 45 minutes before being hauled into a lifeboat by crew.

The ship was scheduled to call in San Juan, Puerto Rico on Sunday.

But, according to reports, guests were surprised after spotting the man swimming in the water and shouting for help.

Tweets from passengers showed the man being rescued.

The Carnival ship, which can carry 2,000 passengers, was on a 7-day southern Caribbean cruise. Puerto Rico and Barbados act as the vessel’s homeport.

If it is shown he deliberately jumped overboard, Carnival is likely to take firm action against him.

In January 2019 a man jumped from the railings of his balcony from Symphony of the Seas while in Nassau, that video went viral and he was permanently banned by Royal Caribbean.

The man is lucky to be alive. Last year, only three of the 23 people who went overboard from a cruise ship were rescued, indicating a survival rate of just over 10 percent.