US cruiseship giant Royal Caribbean Cruises has admitted it is in the dark about the potential impact of the Wuhan coronovirus.

The comments come as a vessel owned by rival Carnival Corp has been quarantined in Japan after 10 people tested positive for the illness, while Royal Caribbean itself has cancelled eight cruises from China up to 4 March.

Chief executive Richard Fain told an earnings conference call: "Obviously the biggest issue of the day is the Wuhan coronavirus.