Russian President Vladimir Putin has said Ukraine and Russia are "finalizing" the negotiations on the prisoner swap, which is expected to be "large-scale."

"We are finalizing our exchange negotiations. I think it will be rather large-scale, and that would be a good step forward towards normalization," Putin said at the Eastern Economic Forum in the Russian city of Vladivostok, answering the question when the exchange between Ukraine and Russia may take place, according to an UNIAN correspondent in Russia.

At the same time, he said Ukrainian MP Viktor Medvedchuk was particularly worried about several people imprisoned in the Russian Federation.

"It was rather difficult for us to make decisions regarding several people, but, based on humanitarian grounds, we are approaching the finalization of negotiations that we see, including with the official authorities," Putin said, adding everything would become known in the near future.

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As UNIAN reported earlier, on August 21, the administration of a Moscow-based Lefortovo pre-trial detention center confirmed that Ukrainian political prisoners Volodymyr Balukh, Stanislav Klykh, Mykola Karpiuk, Oleksandr Kolchenko, and Pavlo Hryb were transferred there from penal colonies.

On August 29 came the reports that Ukrainian political prisoner Oleh Sentsov was also transferred to Lefortovo.

In addition, there was information that Ukrainian journalist Roman Suschenko and 24 POW sailors were also set to be exchanged.

It was also reported that the exchange of held persons should take place on August 29 or August 30. However, on August 30, the Office of the President of Ukraine noted that the process of negotiations on the exchange of prisoners was still ongoing.

"The process of mutual release of held persons is ongoing. Reports about its completion are false. When the mutual release of held persons is completed, the President's Office will report about it via official channels," the statement said.

At the same time, lawyer of certain Russians held in Ukraine Valentyn Rybin earlier suggested the exchange might take place on September 3.