United Russia on Saturday backed Kremlin chief of staff Sergei Naryshkin to become speaker of the State Duma, the party said.
Naryshkin, 57, whose nomination had been widely expected, will take over from Boris Gryzlov, who quit in a move apparently aimed at cooling public anger over Dec. 4 Duma elections that opponents say was rigged in United Russia's favor.
The speaker's post is seen as a nominal one in the top-down "vertical of power" designed by Prime Minister Vladimir Putin, who is expected to return to the Kremlin after a presidential election March 4.
Naryshkin, like Putin a native of St. Petersburg, worked in the 1980s in the economic attache's department of the Soviet Embassy in Belgium. He speaks fluent English and French.
Since 2008 he has headed the Kremlin administration, where he was viewed as a trusted Putin aide capable of keeping an eye on the presidency of Dmitry Medvedev, who is stepping down to switch roles and become prime minister.
Naryshkin's deputy, Vladislav Surkov, a key ideologist of Russia's political system, has taken over as the Kremlin's acting chief of staff.
United Russia won the Duma elections, but its share of the official vote slipped to barely 50 percent from 64 percent in 2007, reducing its majority to just 13 seats.
The election results have been challenged by opposition parties that won entry to parliament and the non-parliamentary opposition, which claims that United Russia's share of the vote was inflated by ballot stuffing and other electoral fraud.
Tens of thousands of people took to the streets Moscow and elsewhere last week to demand a rerun of the elections — the largest political protests during Putin's 12-year rule.
The Duma will reconvene on Wednesday and hold a vote to elect the speaker. Medvedev will address the deputies and other dignitaries in an annual address the following day.
A further round of election protests is planned for next Saturday, with the authorities giving permission for 50,000 to gather in Moscow.