US National Security Agency had been allegedly mining phone records from millions of customers of a subsidiary of Verizon Communications
US President Barack Obama on Friday staunchly defended US government programmes conducting surveillance of Americans' phone and Internet activity, insisting that they were conducted with broad safeguards to protect against abuse.
"Nobody is listening to your telephone calls. That's not what this programme is about," Obama told reporters on a visit to California's Silicon Valley.
He insisted that the surveillance programmes struck the right balance between keeping Americans safe from terrorist attack and protecting their privacy.
Obama stressed that the programmes are overseen by federal judges and by Congress, where senators and representatives are regularly updated on their use, and he said his administration has also instituted audits to make sure safeguards are observed.
The Washington Post reported late on Thursday that federal authorities have been tapping into the central servers of companies including Google, Apple and Facebook to gain access to emails, photos and other files allowing analysts to track a person's movements and contacts.
That added to privacy concerns sparked by a report in the UK's Guardian newspaper that the National Security Agency (NSA) had been mining phone records from millions of customers of a subsidiary of Verizon Communications.
Obama said he came into office with a "healthy scepticism" about the surveillance programmes, but came to believe the "modest encroachments on privacy" are warranted.
"They make a difference in our capacity to anticipate and prevent possible terrorist activity," he said.
The government's internet monitoring programme does not apply to US citizens or residents, he said.
"In the abstract, you can complain about Big Brother and how this is a potential programme run amok, but when you actually look at the details, then I think we've struck the right balance," he said.
Representative Henry Waxman, a California Democrat, said on Friday he thought the administration had good intentions but stressed the programme was "just too broad an over-reach".
'Prism' surveillance programme
The Washington Post said the surveillance programme involving firms including Microsoft, Skype and YouTube, code-named Prism and established under Republican President George W Bush in 2007, had seen "exponential growth" under the Democratic Obama administration.
It said the NSA increasingly relies on Prism as a source of raw material for its intelligence reports.
James Clapper, the director of national intelligence, said the report contained "numerous inaccuracies," and some of the companies identified by the Washington Post denied that the NSA and Federal Bureau of Investigations (FBI) had "direct access" to their central servers.
Microsoft said it does not voluntarily participate in government data collection and only complies "with orders for requests about specific accounts or identifiers".
On Friday, the Guardian said it has seen documents showing how UK's eavesdropping agency GCHQ has had access to the Prism system since at least June 2010. It said the programme has generated 197 intelligence reports in the past year.
GCHQ declined to comment on the story Friday, saying only that it takes its legal obligations "very seriously".
