The National Security Agency and its British counterpart, the Government Communications Headquarters (GCHQ), have been intercepting in-flight mobile phone calls for more than 10 years, according to a report by French newspaper Le Monde.

Citing documents leaked by NSA whistleblower Edward Snowden, Le Monde reports that the agencies began targeting cellphone use on commercial flights in 2005.

A 2012 GCHQ presentation, for example, details a program called Southwinds that gathered cellular activity, voice communication, data and call content on board commercial aircraft. The top-secret document explains that telephones could be spied on when the aircraft was above 10,000 feet, according to Le Monde. The phone signals could be intercepted by secret stations on the ground as they passed through a satellite, it said.

The program reportedly was restricted to regions covered by UK telecommunications company Inmarsat: Europe, the Middle East and Africa.

Inmarsat declined to comment for this story when contacted by FoxNews.com.

Citing an NSA document that detailed plans for “worldwide civilian aircraft tracking,” Le Monde reports that Air France was of particular interest to the intelligence agencies and was targeted as early as 2005.

The airline, however, described the reports of surveillance as false in a statement emailed to FoxNews.com. “Voice communication is not possible on Air France flights,” it said. “In 2007, a GSM communication system was tested on a medium-haul aircraft for a few weeks. As this initial test was not conclusive, the project was abandoned. In addition, the onboard connectivity system implemented on Air France flights will not include voice communications.”

Air France added that flight safety is its main priority. “In line with international industry regulations, on-board connectivity systems are in no way linked to other equipment in the aircraft,” it said.

GSM phones feature in the leaked documents, with the Le Monde report citing an NSA newsletter from 2010. “What do the President of Pakistan, a cigar smuggler, an arms dealer, a counterterrorism target, and a combating-proliferation target have in common? They all used their everyday GSM phone during a flight, and were tracked by the SIGINT system,” it reads.

SIGINT refers to signals intelligence, or information derived from electronic signals and systems.

GCHQ’s 2012 presentation also said data was collected from BlackBerry devices, with surveillance identifying BlackBerry PIN codes and email addresses on an aircraft in 2012. The aircraft’s destination and the airline company were not described in the presentation.

BlackBerry has not yet responded to a request for comment on this story from FoxNews.com.

The 2012 presentation also noted that passenger use of mobile phones had either been enabled or was about to be enabled by 27 companies.

GCHQ said it does not comment on intelligence matters in a statement emailed to FoxNews.com. “All of GCHQ’s work is carried out in accordance with a strict legal and policy framework, which ensures that our activities are authorized, necessary and proportionate,” it added, also citing rigorous oversight by UK lawmakers. “In addition, the UK’s interception regime is entirely compatible with the European Convention on Human Rights.”

The NSA has not yet responded to a request for comment on this story from FoxNews.com.