if you don't mind my saying (so)

if you don't mind my saying (so)

Said before or after a comment that one thinks may make someone else feel upset, offended, or uncomfortable, especially a very direct criticism or compliment. That's a pretty naïve statement, senator, if you don't mind my saying so. If you don't mind my saying, you look extremely handsome tonight.
See also: if, mind, saying
Farlex Dictionary of Idioms.

if you ˌdon’t mind me/my ˈsaying so...

(spoken) used when you are going to criticize somebody or say something that might upset them: That colour doesn’t really suit you, if you don’t mind my saying so.
See also: if, mind, saying
Farlex Partner Idioms Dictionary
See also:
  • if you don't mind me saying (so)
  • if you don't mind me/my saying so...
  • if you don't mind my asking
  • if you don't mind me asking
  • a slap in the face
  • slap in the face
  • smack in the face
  • a smack in the face
  • (I'm) just saying
  • air (one's) dirty laundry in public