them's fighting words
cliché What was said warrants a fight or confrontation. "Fighting" is often rendered as "fightin'" for colloquial or ironic effect. A: "You're dad was a sissy!" B: "Them's fightin' words, pal—I'm gonna knock your block off!" But to suggest that our nation should bend to the will of another, well, them's fighting words around these parts.
Them's fighting words!
Rur. What you just said will lead to a fight. (Said as a threat.) I heard what you said about my brother, and them's fighting words. Put up your dukes. Them's fighting words!