They have been doing it for years. The CIA funded and operates a system called ECHELON which is a signals intelligence (SIGINT) collection and analysis network operated on behalf of the five states to the UKUSA Security Agreement (Australia, Canada, New Zealand, the United Kingdom, and the United States, referred to by a number of abbreviations, including AUSCANNZUKU and Five Eyes.
It has also been described as the only software system which controls the download and dissemination of the intercept of commercial satellite trunk communications.The system Has the software controlling the collection of civilian telecommunications traffic conveyed using communication satellites. It also "kicks in" and monitors and "flags" telephone calls when certain "key words" are use, so If you just happened to mention "Semtex and Prince Harry's underpants,in a telephone conversation , it would "kick in" and monitor and store that conversation. It does this with internet traffic, so you can bet your bottom dollar, that GCHQ in Cheltnam and also Sugar Grove in West Virginia,will most likley be reading this.
They have ECHALON intercept and monitor stations at the Australian Defence Satellite Communications Station (Geraldton, Western Australia)
RAF Menwith Hill (Yorkshire, UK) (the largest Echelon facility in the world)
Misawa Air Base (Japan)US,
GCHQ Bude, (Cornwall, UK)
Pine Gap ,Alice Springs, Australia
Sugar Grove (West Virginia, US)
Yakima Training Center (Washington, US)
GCSB Waihopai (New Zealand)
GCSB Tangimoana (New Zealand)
CFS Leitrim (Ontario, Canada)
Teufelsberg (Berlin, Germany)US
RAF Ayios Nikolaos air base (Cyprus - UK)
Buckley Air Force Base (Aurora, Colorado, US)
Fort Gordon (Georgia, US)
Gander (Newfoundland & Labrador, Canada)
Guam (Pacific Ocean, US)
Kunia (Hawaii, US)
Lackland Air Force Base,San Antonio, US