Vladimir Putin is to be sworn in for a fourth term as President of Russia on Monday after winning the election in March.
He has been in power for 18 years, whether as president or prime minister, and opponents have likened his tenure to the reign of a tsar, or emperor.
Riot police confronted protesters against his rule in Moscow and other Russian cities on Saturday.
More than 1,000 arrests are said to have been made in 19 cities.
The inauguration at the Kremlin in Moscow is likely to be more low-key than in 2012, AFP news agency reports.
Putin is expected to meet only volunteers who took part in his election campaign, the agency says.
Nearly half of the reported 1,000 arrests on Saturday were in Moscow.
Putin was re-elected president with more than 76% of the vote, his best ever election performance, but widespread irregularities were reported by some international observers. Allegations of ballot-rigging had dogged previous elections too.
