"We very much hope that Estonia will halt this unprecedented, illegal action, and will re-think it," Matviyenko said, according to news agency TASS.

"If not, we will certainly take adequate countermeasures. These will be harsh, because it is simply not possible to tolerate this type of activity - harassment of the media. These measures will certainly be very tangible," she told reporters, without elaborating on the form or timescale of the countermeasures threatened.

As reported on ERR News in late November, sanctions against Kremlin propaganda channel Rossiya Segodnya (Russia Today – not to be confused with the RT international TV network, which is also Kremlin-funded-ed.) are, the channel says, forcing Sputnik, a media organization under its umbrella, to move out of their rental office in Tallinn, not least because Estonian banks do not accept Sputnik salary payments.

Matviyenko added that the action has a negative impact on Russian-Estonian relations, implying that the developments are a bowing to U.K. pressure in the light of Prime Minister Boris Johnson's visit to Estonia last weekend.

"I would hope that Estonia has at least some sovereignty, and these statements about Sputnik simply coincided with the visit of the British prime minister to Estonia," Matviyenko said. 

Johnson's visit was officially announced on Friday, December 20, the day before it took place, and nearly a month after the media reports about Sputnik's office rental situation in Tallinn, and nearly two months after the freezing of its bank accounts in Estonia.

According to TASS, Russia addressed Representative on Freedom of the Media Harlem Desir at the Organization for Security and Co-operation in Europe (OSCE), and Dunja Mijatovic, Commissioner for Human Rights at the Council of Europe (CoE), both of which Russia is a member of, on Thursday, over the issue.

The foreign ministry in Estonia said on Wednesday that Sputnik was founded in 2014 by Rossija Segodnya, as its international arm, according to daily Postimees.

Dmitri Kisseljov, Director-General of Rossija Segodnya, is on an EU personal sanctions list due to his central role in propaganda surrounding the 2014 annexation of Crimea from Ukraine, by the Russian Federation, as well as the ongoing insurgency war in the east of Ukraine.

Estonian banks froze Rossija Segodnya accounts in the country in late October.

In December, anti-money laundering authority the Finance Intelligence Unit (FIU) informed individuals who have an employment contract or employment relationship with Rossija Segodnya that knowingly sanctioning or providing services to the organization could result in criminal liability, a stance unprejudiced by Sputnik's media-related categorization and largely linked to Kisseljov's status.

Reinsalu: Estonia continuing with sanctions policy

Foreign minister Urmas Reinsalu (Isamaa) commented that Estonia would not be subject to any foreign pressure on the issue of the impartial application of laws within the territory of the Republic of Estonia.

"As regards the Sputnik issue, the Estonian authorities, in accordance with the Estonian legal order, implement the EU's sanctions policy, which has been imposed on a number of citizens of the Russian Federation who have supported the aggression against Ukraine, and subsequently the sanctions on Sputnik," Reinsalu said on his social media page on Thursday.

"The Republic of Estonia continues to condemn Russian aggression against Ukraine, which is the reason behind the sanctions, and will continue to implement the sanctions policy in accordance with the principles of the EU and its domestic procedures," Reinsalu added.

Last week, Russian president Vladimir Putin said that the claims against Sputnik represented an astonishing display of cynicism which suggested Estonian authorities were afraid of the organization's activities and those of its staff, adding that this was part of a general hypocrisy on the part of "the west" in pointing the finger at Russia for curtailing media freedoms while doing the same itself.

Social media giant Facebook closed over 350 pages related to Sputnik early on this year.

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