This version of the video isn't cropped and includes sound: https://www.youtube.com/watch?v=kgOxzcQ8TFI
I left the following comment, but may as well post it here too.
..
That beluga whale seems so friendly and sweet. This page says it may have been used for "children's therapy":
https://nationalpost.com/news/world/mystery-beluga-branded-a-russian-spy-whale-may-instead-be-a-wayward-childrens-therapy-animal
Morten Vikeby, a former journalist with Fiskeribladet, told his old newspaper he believes Hvaldimir, the spy whale is really Semion, the therapy whale.
In 2008, Vikeby wrote about the Russian therapy whale for the newspaper.
So I did a search and found this Norwegian page, which includes a video of the (possibly same) whale from 2008:
https://fiskeribladet.no/nyheter/?artikkel=66821&ref=rss
Translated to English:
https://translate.google.com/translate?hl=en&sl=auto&tl=en&u=https%3A%2F%2Ffiskeribladet.no%2Fnyheter%2F%3Fartikkel%3D66821%26ref%3Drss