MOSCOW (Reuters) - Russia's lower house of parliament confirmed former president Dmitry Medvedev as prime minister on Tuesday, completing a job swap with Vladimir Putin that has sparked protests against the two leaders' grip on power.
The approval vote, comfortably won by Medvedev as Putin looked on, ignored growing concern in the country that keeping power in the hands of the same men who have led Russia for the past four years will bring political and economic stagnation.
Police led away more than 20 people, including two opposition leaders, when they broke up a peaceful protest near the Kremlin hours before the vote, after detaining more than 700 on the previous two days to keep a lid on dissent.
"They just started to grab people and put them in police buses," said Alexander Delfinov, 40, who was held for hours and ordered to appear in court on Friday, facing a fine or up to 15 days in jail.
Activists regrouped later and were chased around central Moscow by police who hemmed them in and detained dozens more.
In Twitter posts from police vans, prominent opposition activist Alexei Navalny and Ksenia Sobchak, a television host who has fallen out with Putin, said they were among those detained - Navalny for the second time in a day.
The United States said it was concerned by arrests and by clashes that erupted at a rally on Sunday, a day before Putin's inauguration as president, when police beat demonstrators with batons and some protesters wielded pieces of metal fencing and flagpoles.
"We are disturbed by images of police mistreatment of peaceful protesters both during the protests and after detentions," State Department spokesman Mark Toner told a daily briefing in Washington.
Medvedev's confirmation vote in the State Duma, the lower house, was held under tight security, with camouflage-clad riot police guarding the building near Red Square and police trucks and buses parked nearby.
Medvedev stood and nodded to Duma deputies to show his gratitude and then shook hands with Putin. The president smiled and applauded the outcome of the vote, one day after he was sworn in as president for a six-year term.
"I thank you for showing your trust in me," Medvedev told the assembly. "I am absolutely sure that if we work together we can achieve results."
Medvedev, 46, had told the chamber before the vote that Russia must reduce red tape, crack down on corruption and protect property rights to improve the business environment and become more competitive.
"The attitude to business in this country must change drastically," he said before the 299-144 approval vote.
Medvedev pledged wholesale changes in the line-up of the government, without naming any of his cabinet, but said the new team would be one of continuity, pursuing a similar direction to its predecessor under Putin.
He also promised to be open to dialogue with his political opponents, though it was not clear whether he had in mind the non-parliamentary opposition, which has organised the biggest protests since Putin first rose to power in 2000.
Putin's opponents question the legitimacy of his victory in the March presidential election and say his choice of Medvedev as premier is a slap in the face for democracy.
"Everything as always has been decided without consulting the people ... People don't like this," said Ilya Ponomaryov, one of the organisers of protests that were triggered by allegations of electoral fraud last December.
Nikolai Levichev, a senior member of the Just Russia party, criticised the lack of political reform during Medvedev's presidency and said many of the promises he had made - such as on battling corruption and strengthening the independence of the judiciary - had not been fulfilled.
WEAKER PREMIER THAN PUTIN
Putin, 59, gave a brief speech to the Duma presenting Medvedev as an experienced politician who had served Russia well as president and would not let the country down now.
They have been friends since working together in the St Petersburg city administration in the 1990s, and Putin steered the younger man into the Kremlin in 2008 because he was barred from a third successive presidential term himself.
But Medvedev will be a less influential prime minister than Putin, who has remained Russia's dominant leader for the last four years even though the presidency has much more power, including command of the armed forces.
Putin displayed his dominance of the political system by taking the floor after the proceedings to give his own answers to questions deputies had put to Medvedev.
None of the deputies asked about the protests in their questions to Medvedev, focusing instead on issues such as the pension age and state support for science.
Putin and Medvedev face a huge challenge in modernising the country and reforming the $1.9 trillion economy to reduce its heavy dependence on energy exports, which makes it vulnerable to any reduction in the global price of oil.
Putin set out their intentions on Monday by ordering the government to boost investment and shake up state-run industries to usher in a "new economy".
He also set long-term goals that included raising capital investment to no less than 25 percent of GDP in 2015, from the current level of 20 percent, and creating 25 million high-productivity jobs by 2020.
An flurry of decrees also set goals meant to make life easier for ordinary Russians, including raising wages for state workers, making mortgages cheaper, expanding kindergartens and improving health care.
Putin and Medvedev face a battle to quell rivalries between liberals and conservatives, and Putin's picks for the cabinet will go some way to showing how determined and able he is to push through reforms and privatisation.
The U.S. State Department's expression of concern on Tuesday came before Putin, who in December accused Washington of stirring up protest against his rule, meets President Barack Obama at a Group of Eight summit in the United States later this month.
State Department spokesman Toner called for calm on both sides.
"We are also concerned by reports of violence perpetrated against law enforcement by a small group of protesters and we call on all parties to refrain from violence and strongly urge the authorities to respect the rights of freedom of assembly and of speech," he said.