Japan has delayed the start of its next whaling mission by a few days amid media speculation the postponement is to avoid a clash with a visit by the president of the United States.
The International Court of Justice in The Hague ruled last month that Japan's annual Antarctic hunt breached international rules that ban commercial whaling.
But the declaration did not apply to other whaling programmes in the northwest Pacific and a smaller coastal programme.
The fleet for the Pacific hunt was originally scheduled to sail next Tuesday, the day before President Barack Obama is due to arrive in Tokyo.
The Yomiuri Shimbun newspaper said the delay appeared to be an effort to avoid overshadowing the visit.
An official from the fisheries agency confirmed on Thursday that the departure had been delayed, but said it had nothing to do with the president's visit.