The Council of Europe, a human rights watchdog, has lifted its sanctions on Russia in a moral victory for the Kremlin. It meant Russia can take part in the assembly's votes again after its rights were suspended over its invasion of Ukraine in 2014.
Special measures passed on Monday also meant a Russian delegation will be able to vote in Wednesday's election of a new Council of Europe secretary general, where the Russia-friendly Belgian foreign minister, Didier Reynders, is a top candidate, EU Observer reports.
The move was backed by France, Germany, and Switzerland - three leading countries in the 47-member European club, which is separate from EU institutions and which was created in 1949.
France wanted to "preserve the pan-European dimension of the Council of Europe," Amelie de Montchalin, the French EU affairs minister, said also in Strasbourg.
"We don't do geopolitics here, the values that we defend are human rights values," she said.
"We all have the same objective: to defend the common interests of 830 million Europeans ... without any exclusion whatsoever," Liliane Maury Pasquier, a senior Swiss MP, added.
Inviting back Russia would ensure "millions of Russians the protection of the European Court of Human Rights [ECHR]," the council's special tribunal, German foreign minister Heiko Maas said last month.
The Russian delegation is to return despite Russia's ongoing warfare in Ukraine. It is also coming back despite Russia's routine violations of ECHR verdicts.
And it was coming back because Russia was too big to ignore, Piotr Tolstoi, a senior MP on the returning delegation told press.
"We're going to Strasbourg to help our partners overcome the crisis that is undermining this institution, which seems to miss us ... No question in Europe can be solved without its biggest country [Russia]," he said.
Some of the MPs coming back to Strasbourg might be from Crimea, which Russia annexed from Ukraine, he added.
"How can you examine human rights in Crimea without its representatives? To prevent it would be like banning elected officials from the territories of the former GDR [East Germany]," Tolstoi said, referring to the Cold War-era division of Germany.
The Council of Europe had "recognized its errors" on Russia, another senior MP, Konstantin Kosatchev, added. The sanctions were the freak of a "Russophobe minority" in the council, Russian foreign minister Sergei Lavrov said.
The French and German position in Strasbourg stood in contrast to the EU's unanimous decision, last week, to extend economic sanctions on Russia, EU Observer stressed.
It raised the question of whether Russian MPs on EU visa blacklists would be allowed to travel to Strasbourg under special derogations for international events.
And it sent a "very bad message" to the Kremlin, according to Volodymyr Ariev, the head of Ukraine's council delegation.
It said: "Do what you want, annex another country's territory, kill people there and you will still leave with everything," he explained.
"Regrettable and disappointing," Edgars Rinkevics, Latvia's foreign minister, said.
"Latvia opposed the decision because it undermines respect for key values: democracy, rule of law, and human rights," he added.