In the heat of battle in the build-up to May's general election, David Cameron is alleged to have sent an expletive-ridden text message to Boris Johnson.
According to an excerpt of a new book titled Cameron at 10: The Inside Story, author Sir Anthony Seldon reveals that Cameron became increasingly annoyed at his former Bullingdon Club chum in the lead-up to the election.
In an excerpt published in the Mail on Sunday, Seldon quoted a "Number 10 insider":
There was a sense in this building that the PM and Chancellor were getting on taking the difficult decisions while Boris, with his crass bumbling, was lapping it all up and loving twisting the knife.
After Johnson lists in print all the Old Etonians who have gone on to become prime minister, Cameron sends him a text: ‘The next PM will be Miliband if you don’t f---ing shut up.
The author also reveals that Cameron had prepared a post-election losing speech and that on 7 May he had "convinced himself that he will not be prime minister in 24 hours".
How wrong he was.