Snowden leaked information on the National Security Agency's "Prism" cellphone and Internet monitoring program. He has been in hiding, reportedly in Hong Kong.
In an exclusive interview with Australian Broadcasting Corp.'s "Lateline," Assange demanded the Australian government reveal any tie it may have to Prism and said Australians may have been targeted by it.
"We have had indirect communication with his people," Assange said of Snowden. "I don't think it's appropriate at this time that I go into further details."
Assange is holed up in the Ecuadorian Embassy in London, fighting extradition to Sweden where he is wanted for questioning on sexual assault allegations. He has expressed concern about being extradited to the United States because of the millions of pages of sensitive, classified U.S. military and diplomatic documents posted on his whistle-blowing website.
Britain has denied claims its spy agencies were involved in Prism and Assange said Australia must reveal any involvement it may have, ABC reported Tuesday.
"We must ask the question, and the Australian government must answer the question: How many Australians have been intercepted?" Assange said.
He also wondered whether Australian and U.S. agencies pooled information about Australians and whether the Australian government is "involved in this warrantless interception program."