The Russian Central Bank (Bank of Russia) put limits on the transportation of cash to "unfriendly" nations that imposed economic sanctions on Russia in response to its military operation in Ukraine on Friday.

The Bank of Russia posted a statement saying “In response to the partial freezing of Russian reserves, Russia also introduced restrictions on the movement of funds that could be transferred to unfriendly countries, for a comparable amount."

The regulator added that it is basically implementing a "mirror measure," prohibiting foreign investors from moving money, selling assets, and withdrawing funds from the Russian financial system.

Furthermore, payments on Russian business debt and government debt to holders from countries that support sanctions on Russia can now only be made with the permission of a government committee.

Read more: Deutsche Bank slams closing in Russia as impractical

Recently, Western Union announced it will stop money transfers in Russia and Belarus on March 24, giving its customers a 2-week period to prepare for the termination of the service, the company's spokesperson told RIA Novosti. 

Additionally, international card giants Mastercard and Visa have stated that they would cease operations and withdraw all Russian banks from their payment networks following the sanctions imposed on Russia.

Sanctions on Russia amount to a declaration of war: Putin

The wave of sanctions the West has been imposing on Russia as a consequence of its military operation in Ukraine is comparable with a declaration of war, Russian President Vladimir Putin said Saturday, March 5.

"These sanctions that are being imposed, they are akin to a declaration of war," Putin said at a meeting with female flight crews of Russian airlines. 

Addressing NATO's aspirations to expand eastward through Ukraine's accession, Putin highlighted that if Kiev was a NATO member, it would be encouraged to invade Crimea, and its alliance allies would have no choice but support it.