Russian President Vladimir Putin has said that the "excessive demonization" of Soviet dictator Josef Stalin "is one means of attacking the Soviet Union and Russia."

Putin made the comments in the last of four installments of a series of interviews that he gave to U.S. filmmaker Oliver Stone, which was aired on June 15.

Putin said Russia's critics use Stalin's legacy "to show that today's Russia carries on itself some kind of birthmarks of Stalinism."

The Russian president did not elaborate on what he considered to be "excessive" criticism of Stalin, who ruled the Soviet Union from the mid-1920s until his death in 1953 and who was responsible for the deaths of 15 million to 30 million Soviet citizens through executions, labor camps, and avoidable famines.

In the past, Putin has praised Stalin as an "effective manager," and Stalin's reputation in Russia has been growing steadily since Putin came to power in 2000.

A poll in April by the independent Levada research center found that 25 percent of Russians consider Stalin's repressions "historically justified," while another 13 percent said they knew "nothing" about Stalin's crimes.

Forty-seven percent of respondents agreed "it is better to speak less about the repressions and not to dig up the past."