MOSCOW (Reuters) - President Dmitry Medvedev held out an olive branch to opposition protesters on Monday, telling Russia's prosecutor general to study the legality of 32 criminal cases including the jailing of former oil tycoon Mikhail Khodorkovsky.
Medvedev also told the justice minister to explain why Russia had refused to register the liberal opposition movement PARNAS, whose leaders include former Prime Minister Mikhail Kasyanov.
The Kremlin announced Medvedev's decision a day after his ally, Prime Minister Vladimir Putin, won a six-year term in a presidential election. Putin will be inaugurated in May and has said Medvedev will be his prime minister.
Khodorkovsky, who headed what was Russia's biggest oil company, Yukos, and was once the country's richest man, was arrested in 2003 and jailed on tax evasion and fraud charges after showing political ambitions and falling out with Putin.
He received a new sentence in 2010 and is expected to stay in prison until 2016 in a case which Putin's opponents say is politically motivated.
Khodorkovsky's lawyer, Vadim Klyuvgant, told Reuters the true significance of Medvedev's initiative could be judged only when the outcome of the investigation was known.
"There's been so many ... orders that you run out of words to comment," he said by telephone.
"But if ... the prosecutor and the president start to conform with the law, we will know it from the result. The lawlessness of this sentence is so glaring that there's nothing to study there."
Khodorkovsky's former business partner, Platon Lebedev, was also on the list of cases Medvedev ordered the prosecutor general to study and report back on by April 1.
The order followed a meeting last month at which opposition leaders handed Medvedev a list of people they regard as political prisoners and want released from prison.
Medvedev's move could be an empty gesture to the organisers of the biggest protests since Putin rose to power 12 years ago or it could be a parting shot by a man who presented himself as the more liberal of the ruling "tandem" with Putin.
Putin has called Khodorkovsky a "thief" who should sit in jail. Medvedev said last year he saw no threat if Khodorkovsky were freed.
Last year Medvedev asked legal experts to look into Khodorkovsky's case along with other high-profile cases, but the initiative resulted in no review of the court decision.
Prosecutors have said Khodorkovsky stole $27 billion in oil from subsidiaries of Yukos through pricing schemes and laundered some of the money, charges his lawyers dismissed as an absurd, politically motivated pretext to keep him behind bars.
Khodorkovsky, one of the tycoons who made fortunes following the collapse of the Soviet Union in 1991, denies any wrongdoing. He says he has been prosecuted over business practises that were both legal and widely used.
Editing by Timothy Heritage and Elizabeth Piper