International pressure is growing for the Russian government to release nearly 100 juvenile whales which have been kept in small pens in the far east for seven months.
French marine scientist Jean-Michel Cousteau and other experts are meeting government officials in Moscow. They plan to visit the so-called "whale jail" near Nakhodka on Saturday.
There are 11 killer whales (orcas) and 87 belugas in pens at Srednyaya Bay.
A criminal investigation is under way.
While they were in captivity last year, three belugas and one orca disappeared. Greenpeace Russia believes they died, as many of the whales are known to be in poor health.
The environmental group raised the alarm about the whales last October, and four Russian companies linked to the "whale jail" have been accused of violating fishing regulations and cruel treatment of animals.
The whales were caught last year in the Sea of Okhotsk. Greenpeace says the orcas and many of the belugas were probably destined to be sold to marine parks in China, where such tourist attractions are booming.
Individual orcas, often caught illegally, can fetch millions of dollars. Belugas are sold for tens of thousands of dollars.