"The consequences [of withdrawal] would be quite serious. The scenario is currently being worked on at interdepartmental level," the lawmaker said.
At the same time, Kosachev stressed that the Russian government agencies were interested in continued cooperation with the Council of Europe within the framework of existing conventions.
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According to the lawmaker, the withdrawal procedure could be launched in the summer of this year by the Council of Europe's committee of ministers.
"The Council of Europe should on its own deal with the crisis created by PACE," Kosachev underlined, adding that the council's parliamentary arm has so far failed to adopt the measures which could ensure the full restoration of the Russian delegation's rights within the assembly.
Russia has refused to pay contributions to the council until the rights of its delegation to the Parliamentary Assembly (PACE) are restored.
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Russia is part of more than 60 conventions of the Council of Europe, including the convention for the protection of personal data.
Relations between Russia and the Council of Europe, particularly its parliamentary body, worsened after PACE deprived the Russian delegation of the right to vote in the wake of Crimea’s reunification with Russia in 2014, which was not recognized by Western states. Russian officials have repeatedly stressed that the reunification took part via a referendum.
Russian Deputy Foreign Minister Alexander Grushko said on January 19 that lawyers had concluded that PACE documents, which strip Russia of its voting rights, were in breach of the statutory documents of the Council of Europe.