Hundreds of passengers who tested negative for the new coronavirus have begun leaving a quarantined cruise ship in Japan amid heavy criticism over the country’s handling of the outbreak.

One Japanese health expert who visited the Diamond Princess at the port in Yokohama said the situation on board was “completely chaotic”.

US officials said moves to contain the virus “may not have been sufficient”.

Passengers have described the difficult quarantine situation on the vessel.

At least 621 passengers and crew on the Diamond Princess have so far been infected by the Covid-19 virus – the biggest cluster outside mainland China.

The ship was carrying 3,700 people in total.