More cruises on Diamond Princess have been cancelled through to the end of April as the coronavirus outbreak spread to a further 70 people on board.

The latest numbers  confirmed by the Japanese Ministry of Health are in addition to 67 new cases on Saturday to bring the total up to 355.

Additional Asia sailings by Sapphire Princess and Majestic Princess have also been cancelled by Princess Cruises.

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More than 40 itineraries are now affected up until June 11.

Two US government charter flights were deployed to fly out 400 American passengers from Diamond Princess which remains under quarantine in the Japanese port of Yokohama.

A Princess Cruises spokesperson said: “Based on the prolonged quarantine period, and the anticipated time to prepare the ship to return to service, we unfortunately must cancel additional Diamond Princess voyages through the April 20 voyage.

“We are preparing Diamond Princess to return to service April 29, 2020 for the start of Japan’s annual Golden Week celebrations.”

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The line added: “Due to current port restrictions and closures and lack of predictability regarding port availability in our south-east Asia itineraries going forward, we have made the decision to cancel additional Asia voyages on Sapphire Princess and Majestic Princess.”

These include departures from Taipei, Singapore, Yokohama, Hong Kong and Shanghai.

Other itineraries are being changed.

The cruise line is offering full refunds and future cruise credits for cancellations close to departure.

The company said: “Changing a ship’s itinerary involves multiple complex factors, including port and berth availability which is a fluid and dynamic situation, government regulations on immigration and itineraries, calculations on distance and speed required between ports, supply chain operations for provisions, goods, and fuel, and crew rotations.

“These are issues and decisions that teams of people who usually plan itineraries undertake two to three years in advance and are now trying to amend as quickly as possible.

“Simultaneously, other cruise lines are also making itinerary changes and, in some cases, inquiring on the availability of the same ports, adding to the complexity.”

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A spokesperson added: “Princess Cruises can also confirm that the Japanese Ministry of Health has begun to advise of preliminary plans as we move toward February 19 and the end of the quarantine.

“This information was shared by Princess Cruises in a letter to guests and crew members aboard the Diamond Princess.

“Over the last two days plans by the Japanese Ministry of Health for the voluntary disembarkation of guests with medical requirements has begun.

“Twelve guests in this group who tested negative for coronavirus have voluntarily disembarked the ship. Fifty five guests who tested negative within this group have decided to remain on board.”

Diamond Princess has been quarantined in Yokohama with 3,700 people on board since February 3.

David Abel, one of 78 British passengers on the ship, called on the Foreign Office to repatriate them.

He has been posting updates on YouTube from the ship, including regular pleas to be flown home.