...is "fuck you." Because it's the kind of language real people really use and that's good politics, as Goldy here explains:

Rossi’s response was a “fuck you” to Didier and his supporters, and Serkes should be applauded for using the most accurately descriptive term available. This is the way real people speak, and while there are certainly times and places that demand more formal language, politicians and their spokespeople make a mistake by abandoning the vernacular in favor of vague politenesses. Voters crave authenticity, even if that comes with the occasional F-bomb.

Of course, such rhetorical bluntness is not without its risks, especially in a media landscape where the boundaries of public discourse are still rigidly defined by the sticks shoved firmly up the asses of the editors at our once-dominant ”family newspapers.”