Foreign politicians and officials who took part in two G20 summit meetings in London in 2009 had their computers monitored and their phone calls intercepted on the instructions of the British government, according to documents uncovered by United States whistleblower Edward Snowden and obtained by the Guardian.
During G20 meetings in April and September 2009, the Government Communications Headquarters, United Kingdom’s intelligence service, used what one document calls "ground-breaking intelligence capabilities" to intercept the communications of visiting delegations.
Some delegates were tricked into using Internet cafes which had been set up by British intelligence agencies to read their email traffic.
The paper says that the GCHQ penetrated the security on delegates' mobile phones to monitor their email messages and phone calls at the time of the meetings.
The documents suggest that GCHQ supplied 45 analysts with a live round-the-clock summary of who was phoning whom at the summit. Named targets include long-standing allies such as South Africa and Turkey.
The documents say that the then Turkish finance minister, Mehmet Simsek, and possibly 15 other members of his party were targeted.
The meeting of G20 heads of state on April 2 was held to deal with the economic aftermath of the 2008 financial crisis.
The US's National Security Agency also attempted to eavesdrop on Russian leader Dmitry Medvedev as his phone calls passed through satellite links to Moscow, according to the documents.
The revelation comes as Britain prepares to host another summit today -- for the G8 nations -- all of whom attended the 2009 meetings which were subject to systematic spying.
The G20 brings together Argentina, Australia, Brazil, Canada, China, France, Germany, India, Indonesia, Italy, Japan, South Korea, Mexico, Russia, Saudi Arabia, South Africa, Turkey, the UK, the US and the European Union.
The revelation is likely to lead to some tension among visiting delegates of G8 summit. They might ask British Prime Minister David Cameron to explain whether they were targets in 2009 and whether the exercise is to be repeated this week.
The disclosure raises new questions about the boundaries of surveillance by the GCHQ and its American sister organisation -- the National Security Agency -- whose access to phone records and internet data has been defended as necessary in the fight against terrorism and serious crime.
The documents suggest that the operation was sanctioned in principle at a senior level in the government of the then prime minister, Gordon Brown, and that intelligence, including briefings for visiting delegates, was passed to British ministers.
The briefing paper added, "The GCHQ intent is to ensure that intelligence relevant to HMG's desired outcomes for its presidency of the G20 reaches customers at the right time and in a form which allows them to make full use of it."
Two documents explicitly refer to the intelligence being passed to "ministers".
One document refers to a tactic which was "used a lot in recent UK conference, eg G20".
The tactic, which is identified by an internal codeword, is defined in an internal glossary as "active collection against an email account that acquires mail messages without removing them from the remote server", the paper said.
The same document also refers to GCHQ, MI6 and others setting up internet cafes which "were able to extract key logging info, providing credentials for delegates, meaning we have sustained intelligence options against them even after the conference has finished".
This appears to be a reference to acquiring delegates' online login details.
The operation appears to have run for at least six months. One document records that in March 2009 -- the month before the meeting -- GCHQ was working on an official requirement to "deliver a live dynamically updating the graph of telephony call records for target G20 delegates and continuing until G20 (April 2)."
Another document records that when G20 finance ministers met in London in September, GCHQ again took advantage of the occasion to spy on delegates, identifying the Turkish finance minister, Mehmet Simsek as a targe, and listing 15 other junior ministers and officials in his delegation as "possible targets".
The document explicitly records a political objective -- "to establish Turkey's position on agreements from the April London summit" and their "willingness (or not) to co-operate with the rest of the G20 nations".
Image: Former Turkey finance minister Mehmet Simsek, who was one of the targets of spying by UK intelligence agencies, during the G20 meet | Photograph: Reuters
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