Russia\'s opposition Saturday prepared a new mass rally against the rule of Vladimir Putin in a bid to show the protest movement can still challenge the president four months after his inauguration. The Moscow protest march and rally has been dubbed the \"March of Millions\" by organisers, who in reality hope to bring around 50,000 people on the street to show they still have the momentum created by the first protests in December against Putin\'s ultimately successful bid for a third Kremlin term. Split between liberals, nationalists and the extreme-left, the anti-Putin opposition has been struggling with its own divisions and accusations it lacks any coherent message beyond hostility to the Kremlin. This protest, starting at 1000 GMT, is set to have a bigger focus on social injustice than previous actions and for the first time the Russian Communist Party -- the biggest opposition party in parliament -- will be represented. \"The agenda is what we formulated in the spring. We are going to talk about political and socio-economic reforms,\" said one of the protest leaders, Sergei Udaltsov, quoted by the Interfax news agency. A heavy police presence was already evident in Moscow early Saturday as police threw up barriers in the centre of the city. Some 7,000 members of the security forces were to be on duty during the march. The protest could be given extra impetus by the expulsion from parliament of anti-Putin deputy Gennady Gudkov over alleged conflicting business interests, in what the lawmaker\'s supporters said was crude revenge for opposing Putin. It is also the first mass action since the sentencing of three members of punk band Pussy Riot to two years in prison for an anti-Putin protest in an Orthodox cathedral, which has become a rallying cause for many in the opposition. The head of Russia\'s consumer and health protection agency Gennady Onishchenko sought to deter people from taking part, warning the protestors of the risks of catching colds and flu. \"Look around you and check you are near no one who is coughing and sneezing,\" he told would-be marchers. Billionaire tycoon Mikhail Prokhorov, who came third in the March 4 presidential elections and took part in some previous protests, said he would not be joining the march as the opposition had no coherent programme, said radio station Moscow Echo. Thousands-strong protests were also expected in major regional centres including the second city of Saint Petersburg and Yekaterinburg in the Urals. However a protest in the Far East city of Vladivostok only mustered around a few dozen people, police and organisers said.