Moscow ? Less than three weeks before the presidential election, President Vladimir Putin fired his prime minister Tuesday in a surprise stroke that rids the Russian leadership of a top holdover from the Boris Yeltsin era.

The dismissal of Prime Minister Mikhail Kasyanov and his Cabinet also apparently bolstered the authority of Putin’s inner circle of former KGB agents and set the stage for a makeover of the country’s top leadership.

Kasyanov was a strong advocate of the business tycoons many Russians regarded with disdain. His ouster is likely to widen Putin’s already overwhelming lead before the March 14 presidential election by attracting voters who accused Putin of continuing Yeltsin-era policies that the tycoons used to amass great wealth.

Under the Russian government system, the prime minister is primarily responsible for steering economic policy. The dismissal of the prime minister also means the dismissal of the rest of the government.

In a statement broadcast on state television, Putin said he was reshuffling the Cabinet ahead of the vote to “avoid uncertainty in the federal executive structures.” He said the Cabinet’s performance was “satisfactory” but he wants a new government to push reforms further.

“The president wanted to show that he was rupturing ties with the old regime,” said Igor Bunin, the head of the Center for Political Technologies, an independent think-tank.

Lilia Shevtsova of the Carnegie Endowment said that firing Kasyanov could allow Putin to “lay blame on the government for everything he hasn’t achieved during his term.”

The White House, aware of the importance of the U.S.-Russian relationship but increasingly concerned about political developments under Putin, weighed carefully how to respond. Several hours after Putin’s announcement, White House press secretary Scott McClellan was still telling reporters he needed more time to look into the matter.