NSA whistleblower Edward Snowden, an analyst with a U.S. defence contractor, is seen in this still image taken from video during an interview by The Guardian in his hotel room in Hong Kong. REUTERS

The American National Security Agency (NSA) spied at the 2010 G20 summit held in Toronto and Canada was well aware of it, according to documents leaked by former contractor turned whistleblower, Edward Snowden.

Media reports from The Toronto Sun and The Vancouver Sun confirm that Mr Snowden leaked documents which reveal that Canada allowed the NSA to spy at the G20 summit 3 years back. The revelation appears to be politically embarrassing for both the U.S. and Canada.

Mr Snowden's documents, on the other hand, do not specifically point out what kind of information the NSA was in the hunt for during the G20 summit. Mr Snowden has already made a lot of damage to the political reputation of the U.S. recently when he revealed that the U.S. agency did not spare its close allies, countries like Brazil and Germany, as it spied on the top officials from these countries.

CBC aired the report on these leaked documents Wednesday. The report also mentions it was clear the U.S. embassy in Ottawa was transformed into a security command post during the summit, basing on briefing notes leaked by Mr Snowden.

Another major revelation is that the Canadian authorities were well aware of the 6-day spying operation, as the documents quoted that the operation would be coordinated with the "Canadian partner" which was believed to mean the Communications Security Establishment Canada (CSEC), the Canadian equivalent of the U.S. agency.

U.S. authorities refused to comment on the leaked report but continue to justify "gathering information." The spokesperson for the White House National Security Council, Caitlin Hayden, has said that the United States does nothing different from any other country in terms of foreign intelligence.

Canada's security agency CESC head John Forster refused to comment on Canada's involvement in the spying operation during the G20 summit. However, he said that the CESC is legally not allowed to spy on any Canadian or anyone who is in Canada, not excluding visitors.