`` Garden Ring '' road but fell short . A former UK envoy to Moscow says the report is conceivable but improbable . One alleged source says the plan was to use military - grade land mines . The plotters were arrested last week in Kiev , Ukraine , Channel One reports . The announcement comes days before Putin is due to win the presidency .
A former UK envoy to Moscow says the report is conceivable but improbable . One alleged source says the plan was to use military - grade land mines . The plotters were arrested last week in Kiev , Ukraine , Channel One reports . The announcement comes days before Putin is due to win the presidency .