In a statement released on Thursday, the Russian Ministry of Defense announced that after "difficult" negotiations, an exchange of prisoners between Moscow and Kiev was reached.

The statement added that a total of 55 Russian and Donbass soldiers were released and transported to Russia where they are receiving “psychological and medical care” after having been "under threat" while detained by Ukraine.

On the other hand, Ukrainian President Zelensky announced that 215 Ukrainian soldiers were released in the swap. Among the prisoners released by Russia were 10 foreigners including 2 Americans and 5 British soldiers that were transferred to Saudi Arabia, in addition to more than 100 soldiers belonging to the Azov battalion.

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Zelensky pointed out that Turkey and Saudi Arabia mediated the exchange, and claimed that Turkish President Erdogan agreed to have several top Ukrainian commanders under his "protection."

One of the prisoners released by Kiev is Ukrainian politician Viktor Medvedchuk, who led an opposition party that was against Kiev's policies on Russia and was arrested back in April days after the war began.

The exchange comes one day after Russian President Putin announced partial mobilization in Russia and Russia's Ministry of Defense called on 300,000 reservists for military service as Ukrainian-controlled regions in eastern and southern Ukraine declared preparations to hold a referendum on joining Russia. The referendums, which have been anticipated since the beginning of the war, will begin on Friday in the areas of Lugansk, Kherson, Zaporizhzhia, and Donetsk, which are partially under Russian control.