Polls open in vote that could extend Putin's rule

Vladimir Putin made a last-ditch appeal to Russians on Tuesday to vote for constitutional changes that would allow him to run again for president twice, potentially extending his rule until 2036.

Putin made no mention of how the changes could affect his own career. That is consistent with the official get-out-the-vote campaign which has stressed other amendments instead.

State exit polls suggest the changes will be backed by over two thirds of voters, allowing the 67-year-old former KGB officer - if he wishes - to run for another two six-year, back-to-back stints after his current term expires in 2024.

He has already led Russia for more than two decades.