Putin was responding at a televised news conference to a request for comment on leaked diplomatic cables that suggested Russia is undemocratic and corrupt to the highest echelons of power.
"You think that the U.S. diplomatic service is a crystal clear source of information? Do you really think so?" Putin said, in a visibly upbeat mood.
Putin said that, if the West was democratic, then "why was Mr. Assange hidden in prison? Is this democracy?"
He referred to a provincial Russian proverb that equates to "the pot calling the kettle black," in reference to criticism from the West.
Assange is fighting extradition to Sweden on.
Putin, who rules Russia in tandem with President Dmitry Medvedev but wields the most power, reacted with vitriol to the cables' depiction of Russia as a "virtual mafia state" in an interview with Larry King earlier this month.
He said an observation drawn by one U.S. diplomat of Putin playing "Batman" to Medvedev's "Robin" was arrogant, rude and unethical.
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