"This, without doubt, is another act of information war, an absolute dead-end," Konstantin Dolgov told RIA Novosti.
Dolgov stated that Ukraine's move to deprive Russian media of accreditation was breaking international obligations of freedom of speech.
"This, of course, is absolutely unjustified, futile, counter-productive move of authorities aimed to sweep the information field, aimed to block access of millions of their citizens to objective information on what is happening in Ukraine as a whole, especially in the southeastern regions, the information which is provided by Russian news channels," Dolgov said.
"Without doubt, the world community and the OSCE Representative on Freedom of the Media must respond adequately to such a stance by [Ukrainian] authorities," Konstantin Dolgov told RIA Novosti.
Earlier on Saturday, a source in the Ukrainian Security Service (SBU) said that international information agency Rossiya Segodnya, as well as all Russian television channels with the exception of Dozhd independent broadcaster, will temporarily lose their accreditation in Ukrainian governmental agencies.
Earlier this week, Kiev signed a document suspending accreditation of Russian journalists at Ukrainian government agencies.
Since the start of military confrontation between Kiev forces and independence supporters in last April, press freedom in Ukraine has been repeatedly violated, according to the OSCE.