Hackers may have accessed the personal details of P&O Cruises' customers and staff it has been warned, after an attack on its parent company.

Carnival Corporation & PLC, one of the world’s largest cruise operators with a portfolio of nine major cruise lines including P&O and Cunard, detected the incident on Saturday.

The firm has told regulators about the ransomware attack, which got into encrypted parts of its IT systems, and says it is still investigating the incident.

It added that hackers were able to download “certain of our data files” and the hack hit only one part of one of Carnival’s brands.

But the company has declined to say what brand was affected and how many customers or staff have been impacted.

In a statement on Carnival's website, a spokesman says: “We expect that the security event included unauthorised access to personal data of guests and employees, which may result in potential claims from guests, employees, shareholders or regulatory agencies,” it said.

It added: “Based on its preliminary assessment and on the information currently known (in particular, that the incident occurred in a portion of a brand’s information technology systems), the company does not believe the incident will have a material impact on its business, operations or financial results.”

The company has already hired lawyers and is working with “industry-leading cybersecurity firms” to respond to the threat, defend Carnival’s IT systems and start remediation.

It comes at a difficult time for the cruise giant which has been severely impacted by the Covid-19 pandemic.

Its many ships have been forced to stay in port for months as international travel is restricted and passengers are wary about getting back onto the seas. P&O Cruises Arcadia was laid up at Dover's Eastern Docks during lockdown.

Carnival added: “Although we believe that no other information technology systems of the other company’s brands have been impacted by this incident based upon our investigation to date, there can be no assurance that other information technology systems of the other company’s brands will not be adversely affected.”

P&O Cruises and Cunard, both based in Southampton, have been approached for comments.

P&O Ferries, based in Dover, has confirmed that is not owned by Carnival and is not linked to the incident.

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