"I don't think the government needs to comment. (Snowden) did not send us anything," she told reporters. "I won't weigh in."
In an open letter published by the daily Folha de Sao Paulo yesterday, Snowden offered to help Brazil counter US electronic spying but said he needs permanent political asylum to do so.
Snowden, who downloaded a huge trove of classified data documents while working as National Security Agency (NSA) contractor, turned the spotlight on extensive NSA snooping on Brazil.
The revelations infuriated Rousseff, who cancelled a trip to Washington in protest and pushed for a UN resolution aimed at protecting "online" human rights.
In his letter, Snowden did not request asylum from Brazil, but noted that Brazilian senators "have asked for my assistance with their investigations of suspected crimes against Brazilian citizens."
The foreign ministry said it had received no official asylum request from Snowden, who is wanted in the United States for violating espionage laws.
