They aren't the first to kick off outside Downing Street.
But this early morning cat fight was something else.
In the Number 11 corner was the George Osborne-trained Freya facing up to Number 10 southpaw, Larry, in a feline face off.
A Number 10 spokesperson has denied reports of a feud between the two, saying they "coexist" - perhaps in the same way that the UK and Europe "coexist".
Five-year-old Larry is still revelling in his first knockout kill, hitting back against the critics who knocked his apathetic attitude towards rodent control after being brought in last year to help curb the mouse problem at No 10.
There had been rumours that Larry's inability to carry out his duties was to result in an ignoble demotion, forced to job share his Chief Mouser duties with the up-and-coming Freya, Buzzfeed reported.
According to one insider with his paw on the political pulse: "They have not got on for a while, she has clearly taken over the turf. Scuffles between them have been going on."
Round Two awaits...