The storm is due to reach the east coast of the Dominican Republic later today, prompting hurricane warnings on the Caribbean island popular with UK holidaymakers.
A state of emergency was imposed in the US Virgin Islands while other eastern Caribbean islands such as Antigua & Barbuda, St Kitts & Nevis, Guadeloupe and St Maarten were also affected.
Ships with revised itineraries include Royal Caribbean’s Oasis of the Seas and sister ship Allure of the Seas, Freedom of the Seas and Serenade of the Seas as well as Carnival Miracle.
The Puerto Rico Tourism Company said the island was currently under a Tropical Storm warning due to the passing through of Irene.
"All tourist information centres on the island will be available on a 24-hour-a-day basis to offer support to tourists," it said. "All hotels are operating as normal but have activated their contingency plans to protect guests and employees."
Although Luis Munoz Marin International Airport in San Juan is open, airlines have cancelled flights as a preventive measure. "We recommend that arriving and departing passengers call their airline regarding any changes, delays or cancellations," the tourism body said.