A state TV reporter made the announcement during President Vladimir Putin's live Q&A show on Thursday, saying that by "coincidence" the operation began just before the start of the show.
Deputy Prime Minister Alexei Gordeyev said during the show that the operation to fully re-introduce the mammals back into the wild would take at least four months.
The condition of whales kept in cramped conditions in Russia's far east has drawn international concern, and Putin personally ordered authorities to investigate the case and release the animals.
Russian prosecutors have brought criminal charges against four companies keeping the whales.
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