This article in Der Spiegel.

Of particular note:

"Interviewer: What are some of the big surveillance programs
that are active today and how do international partners aid the NSA?

Snowden: In some cases, the so-called Five Eye Partners 4 go
beyond what NSA itself does. For instance, the UK's General
Communications Headquarters (GCHQ) has a system called
TEMPORA. TEMPORA is the signals intelligence community's first
"full-take" Internet buffer that doesn't care about content type and
pays only marginal attention to the Human Rights Act. It snarfs
everything, in a rolling buffer to allow retroactive investigation
without missing a single bit. Right now the buffer can hold three days
of traffic, but that's being improved. Three days may not sound like
much, but remember that that's not metadata. "Full-take" means it
doesn't miss anything, and ingests the entirety of each circuit's
capacity. If you send a single ICMP packet 5 and it routes through the
UK, we get it. If you download something and the CDN (Content Delivery
Network) happens to serve from the UK, we get it. If your sick
daughter's medical records get processed at a London call center …
well, you get the idea.

Interviewer: Is there a way of circumventing that?

Snowden: As a general rule, so long as you have any choice at
all, you should never route through or peer with the UK under any
circumstances. Their fibers are radioactive, and even the Queen's
selfies to the pool boy get logged.

Contrast this with the BBC's website reporting today

"The talks come at a time of growing friction over snooping by the US
National Security Agency on its allies."

Only half the story of course.

Snowden's account of British data collection hasn't yet appeared on the BBC; presumably because TEMPORA is the subject of a DA-Notice

But this has already been widely disclosed, (in Europe) so why the DA-Notice?

Some more info...

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