The Russian press has come up with a variety of theories for President Vladimir Putin's surprise decision on Tuesday to sack the country's government.

Some say that Mr Putin has made a final break with the political era of his predecessor, Boris Yeltsin, while others believe it is an attempt to liven up what is seen as an embarrassingly uncompetitive presidential election.

There is also speculation about the successor to the former Prime Minister Mikhail Kasyanov, with Finance Minister Alexei Kudrin and Defence Minister Sergei Ivanov early favourites.

Putin has shown that he does not intend to simply be happy with what has been achieved, but is genuinely ready to change social and economic policy in a radical way.

Vasily Vitalyev in Trud

It is quite possible that, after much thought, Vladimir Putin has decided on far more radical reform after his re-election... The president's surprise political move can also be taken as a signal to the old Yeltsin-era elite - to which the sacked prime minister undoubtedly belonged - telling them that their time is up and that they have no serious chance of holding on to any kind of top position in Russian politics after the presidential elections.

Gazeta

Kasyanov's sacking is symbolic of the president's final break with the Yeltsin past... But there is another, no less important reason for his dismissal. With this step, the Kremlin is trying to introduce an element of intrigue into the presidential elections and prevent them from turning into a PR disaster for Putin... [as] the complete absence of any serious competition at the elections was threatening to inflict serious political losses on Mr Putin.

Aleksandr Budberg and Mikhail Rostovsky in Moskovsky Komsomolets

What exactly led the president to pull the chair out from under the current prime minister is clear: a few days before the elections, the Kremlin is trying to do everything possible to liven things up a bit.

Almira Kozhakhmetova in Novyye Izvestia

Sacking Kasyanov looks like an effective pre-election move by the president... It is clear that this is not the resignation of the government - a routine procedure following the elections - but the specific sacking of Mikhail Kasyanov.

Maksim Glikin in Nezavisimaya Gazeta

The president did not say who he would propose to the State Duma [lower house of parliament] as the new prime minister. Observers are saying the most likely choices are Deputy Prime Minister Alexei Kudrin and Defence Minister Sergei Ivanov. In the same league, but with slimmer chances, are State Duma speaker Boris Gryzlov, Emergencies Minister Sergei Shoygu, and [acting Prime Minister] Viktor Khristenko himself.

Izvestia

Recently two names have figured as the main candidates for prime minister: Defence Minister Sergei Ivanov and Finance Minister Alexei Kudrin. Old government hands say the latter has long-standing friendly relations with Vladimir Putin... But Kudrin is an economist, not a public figure. If we follow PR logic, the powerful Sergey Ivanov, who understands nothing about budgets and surpluses and deficits, will be of greater use here.

Almira Kozhakhmetova in Novyye Izvestia

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