Boris Johnson was the Mayor of London during Monos' graffiti attacks on London landmarks in 2012. When he gave a statement to the press, he promised that the miscreant would be sorry for his actions. (COMIC: Sticks & Stones)
Behind the scenes
In the real world, Boris Johnson succeeded Theresa May as Prime Minister of the United Kingdom following her resignation in 2019.
After Prime Minister Boris Johnson announced the assembly of four new committees to coordinate various aspects of the COVID-19 outbreak that would report their work in daily meetings dubbed "C-19 meetings", some media outlets reported the reaction of Doctor Who fans who noted a similarity between that of the sinister Department C19.[1][2]
Russell T Davies for the Who at Home rewatch wrote Revenge of the Nestene, in which the last trace of the Nestene Consciousness merges with someone blonde in Westminster. It is implied that they are Boris Johnson.