EU foreign policy chief Federica Mogherini said on Saturday the bloc considered the polls "illegal and illegitimate and will not recognise them."
Some analysts say that after 18 years of leadership -- both as president and prime minister -- Putin fatigue may be spreading across the country.
"755 people must stop their activities in Russia," said the Russian leader.
Trump has repeatedly denounced as "fake news" the accusations that members of his circle coordinated or colluded with Russian officials.
Russia's Investigative Committee say it is probing an "act of terror" but add it will look into all other possible causes of the blast.
With Russians worried about their shrinking purchasing power and a presidential election due next year, perceptions about the economy and its outlook are...
Scans and photos leaked on various social networks show a golden medal with an engraved warship and warplanes against the outline of Syria
"The process is very fragile, discussions are under way," says Russia's Dmitry Peskov.
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