The Asahi newspaper is reporting the annual round of research whaling could be suspended because of the poor condition of the fleet’s ageing factory ship.
It says the fisheries agency wants to undertake large-scale repairs to the Nisshin Maru.
The process could take months and may mean the annual whaling hunt in the Southern Ocean, which usually begins in late November or December, could be called off for the year.
If it is, it will be the first time in 25 years the Japanese have not embarked on an annual round of so-called research whaling.
The fisheries agency has told the ABC it will not confirm the media report.