Ryanair has cancelled all flights to Morocco through February 1, 2022 due to a "lack of clarity" from the Moroccan Government.
Morocco recently suspended all flights going into the country owing to the spread of the Omicron variant.
The flight ban will last for two weeks from November 29 to December 13.
The Moroccan Foreign Ministry said the flight ban was to "preserve the gains made by Morocco in the fight against the pandemic and protect citizens".
Ryanair said it had contacted all affected passengers and made them aware of their options, which include a free flight change or refund.
The UK Foreign Office advises Brits to contact their airline or tour operator for advice on returning to the UK.
The Foreign Office says: "The Moroccan Government has announced the suspension of all flights and ferry services to Morocco with effect from 11:59pm on 29 November for a period of two weeks.
"Some airlines, including Air France, Tui, Royal Air Maroc and Transavia, are continuing to provide commercial flights out of Morocco. Contact the airlines direct to make a booking.
"British nationals in Morocco who require consular assistance should call the British Embassy on + 212 (0) 537 63 33 33 and follow the voice menu for "option 4 - consular assistance'."
In October, Morocco banned flights from the UK, Germany and Netherlands due to concerns about the coronavirus rates in the countries.
So far 160,000 Ryanair fliers have been impacted by flight cancellations with another 230,000 likely to be hit by more cancellations in the new year.
Ryanair's Director of Commercial, Jason McGuinness, said: "We deeply regret this disruption to our passengers from these cancelled Morocco flights until February 1, 2022, due to a lack of clarity from the Moroccan authorities on what to expect beyond their initial travel ban ruling to December 13.
"Ryanair regrets the unnecessary disruption caused and apologises to all of our passengers for this outcome, which is entirely beyond our control."
