Two men with Chechen links have been formally charged with attempting to kill Russian Prime Minister Vladimir Putin, Kommersant daily reported on Tuesday.
Adam Osmayev and Ilya Pyanzin earlier confessed to planning to murder Putin on the orders of Chechen warlord Doku Umarov.
The men were detained in the Ukrainian port city of Odessa after a fellow suspect was killed in a an appartment explosion there in January.
They were charged with forming a terrorist group and plotting a terrorist attack after investigators found compelling evidence of their guilt, a spokesperson for Ukraine's Security Service, the SBU.
News of the alleged plot came a week before the March 4 presidential polls in which Putin claimed a landslide victory amid widespread allegations of electoral fraud.
Some analysts and opposition figures have said the plot was fabricated to boost Putin's percentage.
Reports of thwarted assassination attempts against Putin appeared in advance of every election since the former KGB agent came to power in 2000.
A number of Russian media said Chechen militants were planning to kill Putin, then the caretaker president, during his first presidential run in February 2000. Russia's security services neither confirmed nor denied the information. Ahead of Putin's re-election bid in 2003, Britain said it thwarted a suspected plot by two renegade KGB officers to assasinate Putin while on a foreign trip.
Putin was "unaffected" by the latest plot, his spokesman told the tabloid Komsomolskaya Pravda last month.
The men were also planning to murder controversial Chechen leader Ramzan Kadyrov, Kommersant reported earlier this month.