Russian President Vladimir Putin.Contributor/ Getty ImagesPutin is repeating a Soviet-era mistake, which is ruining Russia's economy, Poland's foreign minister said.Speaking at Davos, Radoslaw Sikorski said Putin was overspending on the military and bankrupting Russia."He was very insistent that this mistake should not be repeated. And he's doing exactly that," he said.Russian President Vladimir Putin is copying Soviet-era approaches that bankrupted the USSR and that he used to criticize, according to Poland's foreign minister.Speaking on a panel at the World Economic Forum in Davos on Thursday, Radoslaw Sikorski said "Putin is repeating the mistakes of Soviet leadership" in regards to his invasion of Ukraine."The Soviet Union took on the West and lost," he said.Sikorski said that Putin "is on the record saying that under Brezhnev, the Soviet Union overspent on the military and bankrupted the country."He said Putin was "very insistent that this mistake should not be repeated.