According to the documents provided by NSA whistleblower Edward Snowden, the British intelligence agency has been actively involved in spying the phone and online communications by various foreign delegates - even those of allied countries - in order for British officials to gain an advantage in the debates.
The agency even set up Internet cafes equipped with email interception and key-logging software so that they could both take a peek into the emails sent and received by the foreign representatives and harvest their login credentials in order to continue to have access to their email accounts, and has also managed to compromise the communication they carried out via their BlackBerry mobile devices.
Other documents revealed that South African delegates were definitive and that the Turkish finance minister and 15 of his junior delegates were possible targets of the GCHQ, and that the monitoring of their computers and communications was not effected because they were suspected of criminal wrongdoing, but for political reasons.
The documents also revealed that this entire operation was approved at a "senior level in the government" and that British ministers received summaries about the collected intelligence from 45 dedicated analysts that were sifting through the acquired information round-the-clock.
Finally, the agency has also noted that the NSA has tried to intercept and decode the encrypted phone calls made by Russian delegates and the then Russian president Dmitry Medvedev to Moscow.
"There have often been rumours of this kind of espionage at international conferences, but it is highly unusual for hard evidence to confirm it and spell out the detail," The Guardian reporters pointed out, adding that their report will surely raise many questions at the upcoming G8 summit hosted by the U.K. and scheduled to take place on June 17 and 18 in Lough Erne in Northern Ireland.