Thousands of people laid flowers and lit candles on Saturday on a bridge near his murder site.
The authorities agreed procession of up to 50 thousand people. The procession is planned to move from Kitaygorodskiy pr-d to Moskvoretskaya embankment, the Bolshoy Moskvoretskiy bridge, and it will end on the Malyy Moskvoretskiy bridge. Participants will reportedly start gathering at 02:00 p.m. Moscow time (11:00 a.m. GMT) and the march itself is scheduled to start at 03:00 p.m. Moscow time (12:00 a.m. GMT).
Moscow authorities said the police would take all necessary measures to ensure the security of the protesters.
In addition, a Moscow official said that the previously agreed opposition march in not to take place today, as the opposition withdrew its bid.
Nemtsov was deputy prime minister under Russia's former President Boris Yeltsin in the 1990s, a co-chair of the RPR-PARNAS (Republican Party of Russia — People's Freedom Party) since 2012, and one of the leaders of the liberal Solidarnost movement.
An investigation into the politician's murder was launched by the Russian Investigative Committee, which is considering several versions, including possible connection between Nemtsov's death and the events in Ukraine, the Charlie Hebdo shooting in Paris and his business activity.
Nemtsov will be buried on March 3 Troekurov Cemetery in Moscow. A memorial service will be held in the morning at the Sakharov Center.