Mass march planned against Putin Russian Prime Minister and presidential candidate Vladimir Putin (L) is greeted by his supporters and campaign staff during night after the presidential election day on March 5, 2012. MOSCOW, March 15 (UPI) -- An opposition leader in Moscow called for a million-man march in Moscow two days before Vladimir Putin is to be sworn into office as president. Sergei Udaltsov, a left-leaning opponent of Prime Minister Putin, said demonstrations against Putin's political dominance would culminate in a mass May 5 protest. "Let's come out to one of Moscow squares and not leave if we're numerous enough," he was quoted by Russia's state-run news agency RIA Novosti as saying. If the authorities have ignored a rally of a 100,000, we need to bring out more. Udaltsov was sentenced to 10 days in jail Thursday following his arrest during a weekend demonstration. Human Rights Watch had said that while the Kremlin was tolerant of dissent during the campaign season, activists were roughed up by authorities after the election. Putin secured a third non-consecutive term as president in an early March election. Opposition groups had said they wouldn't recognize Putin's victory. He's to be sworn in May 7.