Censor.NET reports citing BBC.
German Chancellor Angela Merkel is due to meet Vladimir Putin in Russia for the first time since 2015.
The meeting, at Putin's summer residence in Sochi, comes at a low point in bilateral relations over the war in Syria and Russia's annexation of Crimea.
They are expected to discuss both issues during their meeting - but no breakthroughs are expected.
Putin will then meet Turkish leader Recep Tayyip Erdogan on Wednesday.
Ties between Russia and Germany have worsened since Russia's 2014 annexation of Crimea in Ukraine, with Germany being a driving force behind the EU sanctions imposed in response.
The pair, who are among the most powerful world leaders, have crossed paths at international summits recently.
But this meeting - with the official purpose of discussing the G20 summit of world leaders to be held in Hamburg in July - is the first trip Merkel has made to Russia in two years.
Merkel wants Russia to seek an end to the conflict in Ukraine by using its influence on pro-Russian separatists, and also needs Moscow's cooperation to bring peace to Syria, the BBC correspondent in Berlin, Damien McGuiness, says.
But President Putin equally needs Mrs Merkel's support in to lift the EU's sanctions, our correspondent adds. Mr Putin is also keen to hear her opinion of US President Donald Trump, whom she recently met.
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