It was a quote which shocked the political Commentariat. And sent a shiver through European capitals and British politics.

An unnamed No 10 source was claiming there were "all sorts of things" they could do to scupper a delay to Brexit.

The remark was carried in a right-wing magazine, The Spectator. But where did it come from?

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Amber Rudd reckon she knows. The former Home Secretary, who has quit the cabinet and the Tory party, has pointed the finger at Dominic Cummings, Boris Johnson's controversial aide.

Ms Rudd told the Today programme: "It sounds angry and desperate. And the language that is used, I do not believe should be the language of a UK Government. There's a fair amount of speculation about where it came from.

"But since it hasn't been denied by Number 10, and no young woman spad [special adviser], for instance, has been marched out of Downing Street, one can only assume it's come from the centre, from the Prime Minister's adviser.

"And the style of it seems to imply that."

Asked if she thinks it was written by Mr Cummings, she said: "I think Dominic Cummings, yes, because otherwise it would have been heavily denied and heads would have rolled. So clearly it's come from them, it's in their style.

"It reveals that there doesn't appear to be an actual plan at all. Instead, what they're doing is angrily, apparently, begging the EU not to support a delay which will be required because of the position that Parliament has taken.

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"And I urgently would ask the Prime Minister to take control of this and give us some clarity and some dignity and diplomacy on what is taking place."

Ms Rudd told Today: "First of all, Government has consistently been saying since the Benn Act was passed that they have a cunning plan.

"And many of us have been confused by the idea of saying that they will obey the law but we are definitely leaving on October 31. And I don't think that this memo suggests that there is any plan."

She added: "What they're doing in fact is going down on one knee and begging EU members not to participate in this."