Iran's Supreme Leader Ayatollah Ali Khamenei
Iran's Supreme Leader Ayatollah Ali KhameneiReuters

Israeli, British, and US intelligence organizations have been working together to monitor Iranian leaders, according to a document leaked by National Security Agency (NSA) dissident Edward Snowden Sunday. 

The document, leaked on The Intercept website, reveals a working relationship between the Sigint 8200 unit - referred to as the Israel Sigint National Unit, or ISNU - with the NSA and the British Government Communications Headquarters (GCHQ).

“The respective NSA-ISNU and GCHQ-ISNU bilateral relationships had gotten to the point that each participant recognized the need for the trilateral engagement to advance this specific topic,” the document, dated April 12, 2013, notes.

However, while the British intelligence heads heavily advocated an official trilateral relationship between the three countries, the NSA had reservations over full cooperation, and the three continue to share information as independent bodies instead of working as one unit, the document says. 

Despite this, trilateral discussions between the agencies were held for the first time in January 2013 to assess the full threat of the Iran nuclear program, as well as Iranian cyber attacks against US financial organizations, which Israel indicated Tehran was fully aware of.

Meanwhile, the NSA has worked closely with GCHQ during several key events, it added, including "the storming of the British Embassy in Tehran; Iran’s discovery of computer network exploitation tools on their networks in 2012 and 2013; and support to policymakers during the multiple rounds of P5 plus 1 negotiation on Iran’s nuclear program." 

It concluded that it "could not rule out" more operations against Iran, given the volatile nature of the Islamic Republic's Islamist regime and the development of its nuclear program. 

Snowden, a former NSA contractor, is wanted by the United States on espionage charges after leaking a mass of secret NSA documents.The 31-year-old fugitive is in asylum in Russia, where he has been granted a three-year residency that allows him to travel abroad.

Several of his leaks have indicated secret "deals" between the US and world powers for matters of national security; in one such alleged deal, the NSA passed to 8200 the private conversations between Palestinian Arabs and Israeli Arabs and their American relatives for monitoring.