In a research note that attracted wide attention, Moscow brokerage Otkritie suggested that President Dmitry Medvedev could step down early, allowing Putin to assume the presidency on an acting basis until the March 4 election.

Otkritie analysts Vladimir Tikhomirov and Tom Mundy also wrote that Putin could stand down and delegate the day-to-day running of the government to a senior technocrat for the duration of the campaign.

Putin's spokesman, Dmitry Peskov, dismissed any suggestions that the 59-year-old premier would take a leave of absence, and questioned any interpretation of Russian election law that suggests otherwise.

"Putin continues to work as chairman of the government. If any events have an entirely campaign-related nature, he will take a vacation," he said. "But on the whole he will carry out his day-to-day duties as prime minister. He does not have to take any vacation."

Reuters