Russia faces to watch: Alexei Kudrin
The BBC looks at some of the key figures emerging in Russia's political scene.
For more than a decade, Alexei Kudrin was part of the ruling elite, serving as finance minister under Vladimir Putin, including two spells as deputy prime minister. In the 1990s, the two close friends worked together in St Petersburg's city administration.
Mr Kudrin has always been seen as a liberal, and was for years the only member of the government who felt safe enough to criticise the ruling United Russia party openly, though cautiously.
Well-known around the world as a top-flight economist, Mr Kudrin has always stood for a free-market economy and against populist spending initiatives.
In September 2011, Mr Kudrin resigned after a public row with the president over spending.
When Mr Kudrin criticised Dmitry Medvedev's plans for boosting the military and social welfare budgets, the president called on him to resign, which he did the next day.
Yet as the row with Mr Medvedev was broadcast on state-controlled TV, many political commentators suspected it was staged.
Mr Kudrin has since tried to establish his political credentials by saying he is ready to take part in the establishment of a new and influential liberal political party, but so far he has not taken any practical steps in that direction.
In December 2011, he appeared at an opposition rally in Moscow and gave a speech in which he described recent parliamentary elections as unfair and offered himself as mediator in negotiations between the protesters and Mr Putin.
As yet, no such talks have taken place.