According to information leaked by Snowden, President Dilma Rousseff's communications with aides were intercepted, the computer network of state-run oil company Petrobras was hacked and data on billions of emails and telephone calls flowing through Brazil were monitored by the NSA.
"For our investigation, questioning Snowden is a top priority," said Jose Alberto Freitas, the head of the intelligence sector of Brazil's Federal Police, before a Senate committee investigating the NSA spy program. "He could provide technical details that will help our investigation advance."
Ricardo Ferraco, who heads the committee, said that on Thursday he will ask the Russian government for permission to speak to Snowden via a video conference.
Snowden received asylum in Russia in August.
"We have to go to the Snowden who is the primary source," Ferraco said, adding that if the committee is not allowed to meet with Snowden, "I doubt our investigations will move forward."
The fallout over the spy programs led Rousseff to cancel a planned visit to the U.S., where she was to be the guest of honor for a state dinner.
Rousseff last month spoke at the United Nations General Assembly and called for international regulations on data privacy and limiting espionage programs targeting the Internet.