I agree with John Gruber on this, POTUS's allegations are the actions of a man whose elevator does not go all the way to the penthouse of Trump Tower.
Do you have a source for this?
"Intelligence sources told The Telegraph that both Mr Spicer and General McMaster, the US National Security Adviser, have apologised over the claims. "The apology came direct from them," a source said.
General McMaster contacted Sir Mark Lyall Grant, the Prime Minister's National Security adviser, to apologise for the comments. Mr Spicer conveyed his apology through Sir Kim Darroch, Britain's US ambassador."
Intelligence sources told The Telegraph that both Mr Spicer and General McMaster, the US National Security Adviser, have apologised over the claims. "The apology came direct from them," a source said.
It's based on an anonymous source.
Here's another quote from that same article:
"Three intelligence sources have informed Fox News that President Obama went outside the chain of command - he didn't use the NSA, he didn't use the CIA, he didn't use the FBI and he didn't use the Department of Justice - he used GCHQ."
So we're going to discard what several anonymous sources said, but we will believe what some other anonymous source said?
There's a denial.
And there's saying it's "nonsense, utterly ridiculous and should be ignored" which goes beyond a mere denial. For GCHQ, this is very strong language.
To say they didn't, and then get found to have done, will be infinitely worse.
It just makes no sense.
Everybody spies on everybody, everybody accuses everybody, everybody lies about both, gets caught and mostly doesn't care. The allegations prove just as much as the denials - nothing. Eventually one side will be caught lying, and nothing will happen to them.
Like if Donald Trump said "to most people in our area right now, the sky appears blue", he would probably be right, despite his general propensity for lying and manipulating other topics
And I think there's something more. I would read into their statement that they are very angry.
This is my interpretation too (as a fellow Brit). As far as diplomatic language goes, it's one step short of saying "He's a bit of a twat".
I would think that "nonsense" implies "untrue". I.e. it is "The subset of untruths that also are logically inconsistent"
We are splitting hairs of the fine parsing of the wording from GCHQ, when words of any kind are highly unusual.
It's way beyond just stating that they're untrue.
Whether Trump, Obama, Clinton or even Pailin had said it, and whether they gave evidence or not, it's obvious that it happens.
Not from an smoking-gun evidence based standpoint, but from a knowing history, and people, and such agencies priorities and how lose their leashes are standpoint.
When it comes to such agencies, evidence is the last thing one would find. It's not like their advertise their operations except in extreme fiascos. But such wiretapping is completely in agreement with the essence of what they do.
Trump's claim is not "GCHQ spied on me" - I agree this is the kind of thing that spy agencies do.
Trump's claim is "GCHQ spied on me not for the UK gov, but for Obama".
It's ridiculous to think GCHQ did this.
Lacking concrete evidence, that's exactly the kind of thing you should base your beliefs of specific events on.
"just before" reads to me as the starting point in his accusation, not the ending point?
It's as if he watched Star Trek, then demanded an investigation into Romulan incursions into the Neutral Zone.
Because it would be highly embarrassing for the UK if that actually happened, and would severely damage the special relationship.
Apparently this was caused by the local policeman being from the UK and he'd been going round using the term for years and the locals had interpreted it as something nice.
(I got asked this very question by an American relation a few years back.)
NB I don't think they did snoop on Trump, but if anyone was going to do it from the UK it would presumably be GCHQ.
EDIT: My point is much larger than whether or not they wiretapped Donald Trump. My point is that what an intelligence agency says about what it's doing is completely irrelevant because it has very low correlation to what they actually do.