A leading cruise ship operator has been accused of threatening more than 900 crew with being fired and rehired if they do not accept reduced terms and conditions.

The Nautilus union said Carnival UK has notified authorities in the UK and Bermuda of its intention to change employment terms and conditions for 919 crew across 10 vessels.

Crew on the affected fleets includes those working on P&O Cruises and Cunard, on ships such as the Queen Elizabeth and Queen Mary 2, the union said.

Nautilus has written to the company calling for it to withdraw the threat of fire and rehire and engage in meaningful negotiations.

P&O Cruises is an entirely separate company to P&O Ferries, which was embroiled in a dispute over the sacking of hundreds of workers by its owner DP World in March 2022.

Louise Haigh, the shadow transport secretary, said: “It has been almost two years since P&O Ferries illegally sacked 800 workers and replaced them with agency workers paid less than the minimum wage.

“Now history is repeating itself. The lives of hundreds more seafarers are once again being upended by bad bosses who know they can get away with it.

“Ministers have sat on their hands and ignored warning after warning that this would happen again unless they stepped in to change the law. The blame lies with them.

“Labour will end this cycle and end fire and rehire practices for good.”