Families are set to miss out on cruises after Cunard said all passengers must have two Covid jabs in order to travel.
The British cruise line’s policy means children and teenagers from the UK are effectively banned from travelling because they are only eligible for one dose of the vaccine.
It comes as rules are set to change on Monday to allow travel between the UK and long-haul destinations such as Mexico and South Africa.
Forty-seven countries will be removed from the red list at 4am, meaning arrivals from those locations will no longer need to quarantine in a hotel.
Meanwhile, the Foreign, Commonwealth and Development Office has lifted its advice against non-essential travel to a further 42 countries and territories.
Travel countries on the red, green and amber list
Cunard’s policy previously stated that all adults over the age of 18 needed to be fully vaccinated, while children aged five to 17 who were not fully vaccinated could travel with a negative PCR result. Children under five were allowed to travel as long as their parent or guardian was fully vaccinated.
But a fortnight ago, the policy was changed, meaning under-18s can now only travel if they are fully vaccinated with two doses. This means children from other countries, such as the US and Germany, where both shots of the vaccine are licenced for children, would be eligible to travel if they have had both jabs.
Meanwhile in Britain, healthy children aged 12 to 17 are only eligible to have one dose of the vaccine – but even if they have had one jab, they would still not be eligible to board a Cunard cruise ship.
One family told of their anger after they were forced to cancel their £20,000 holiday because they could no longer take their grandchildren.
Josephine Johnston, 67 and her husband Ray, 70, from Kent, were set to travel to the Canary Islands for two weeks with five relatives.
Their trip on the Queen Elizabeth cruise ship, which had already been postponed because of the Covid pandemic, was switched to Dec 23. But the couple cannot now go with their two daughters, son-in-law and granddaughter and grandson because he is just 14 years old.
"I feel very angry about this, not just for me but all the other families as well," Mrs Johnston said. "It’s awful –they have ruined Christmas. We cannot book any other holidays at this short notice. Children have had enough to deal with during the pandemic, and they should not be made to feel guilty."
A Cunard spokesman said: "We are sorry for any disappointment caused by our recently updated vaccination policy. Our health protocols are designed to adapt as needed to the changing public health situation related to Covid-19. We therefore continue to work hand in hand with the authorities and regional partners in the destinations we visit to ensure we comply with their evolving local protocols.
"Following a review of the current entry requirements of the ports on our planned itineraries over the coming months, it was necessary to make a change to our previously stated vaccination policy."