Keith said: [Unionist would not accept it] Who was surprised?

I said: May, Davis and the whole UK negotiating team, apparently.

Keith said: It was not true that the UK ever agreed to it

Strictly speaking that is right, since May would have been the one to make such a formal announcement. But if the UK would not have been about to agree the DUP telephone call was of no significance whatsoever and therefore any leak of the wording would not have affected anything because, you claim, there was not going to be an agreement.

Given that the DUP did make the call and it does appear to have an effect, I think I am right is my original response.