Vladimir Putin took oath of office on Monday to start his fourth term as Russian president.

"It is my duty and the meaning of my entire life to do everything for Russia, its present and future, to ensure that it is peaceful and prosperous, to preserve and perpetuate our great people, and bring prosperity to every household in Russia," Putin said at the inauguration ceremony in the Grand Kremlin Palace.

He said Russia needs to build a free society. "We need breakthroughs in all areas of life... Such progress can only be achieved by a free society that embraces everything new and advanced, and rejects injustice, stagnation, ignorant protectionism and bureaucratic deadness," he said.

The president said Russia must focus its energy on working out a solution that raises its competitiveness in economic growth and technology development.

Putin won a landslide victory in the March 18 presidential election.

Some 6,000 people were invited to the inauguration ceremony, including members of the government, deputies and senators, judges of the Constitutional Court, heads of diplomatic missions and representatives of the clergy and youth organizations.

Putin is expected to name Dmitry Medvedev as his new prime minister and submit his nomination to parliament later on Monday.