Mayor of London
David Cameron was initially horrified at the prospect of Boris Johnson standing as London mayor in 2008. When a series of high-profile candidates refused to run, Cameron turned reluctantly to Johnson.
Broken Britain
Johnson described Cameron's key idea about Broken Britain as "piffle". "If you believe the politicians, we have a broken society, in which the courage and morals of young people have been sapped by welfarism and political correctness. And if you look at what is happening at the Beijing Olympics, you can see what piffle that is."
Of Cameron's "in this together" catchphrase, he said: "I am vain enough to have a feeling that he nicked it from me."
Conservative party loyalty
Cameron was always a true blue. Johnson flirted with the SDP at Oxford – to win election as president of the union
Europe
Nick Boles, a key Cameron ally, texted Johnson the threat from the Godfather: "La vendetta è un piatto che va mangiato freddo" ("Revenge is a dish best eaten cold") The anger in 2009 was over Johnson's support for a referendum on the Lisbon treaty just as Cameron carried out a U-turn.
Cheap holidays
Johnson outed the cabinet's policy guru and fellow Etonian Oliver Letwin for snobbishness after he privately said: "We don't want more people from Sheffield flying away on cheap holidays."
The tube
Johnson said last week that the government was being "lily-livered" in not doing more to prevent tube strikes by toughening up employment laws.
Heathrow
Restricting growth of airports will do "serious longterm damage to the economy", Johnson said. Also questioned the high-speed rail line to the north which is meant to ease the pressure on Heathrow. "You cannot take a high-speed train to Beijing or Sao Paulo."
Jamie Oliver
Shortly after Cameron had praised Oliver's school eating campaign in 2006, Johnson said: "I say let people eat what they like. Why shouldn't they [parents] push pies through the railings?"
Bullingdon Club
Johnson was an enthusiastic participant and was among a group of members of this Oxford society who scarpered from a restaurant after a pot plant was thrown through a window. A "tired" Cameron had gone to bed.
Social cleansing
The coalition's cuts to housing benefit prompted Johnson to warn last October: "What we will not see, and will not accept, is any kind of Kosovo-style social cleansing of London."
