we have to do lunch sometime

we have to do lunch sometime

We should really get together at some point in the future, ostensibly to have lunch. A clichéd, noncommittal expression often associated with upper-class people. A: "I'd love to sit down with you sometime and go over some ideas I have for the business." B: "Oh yes, of course. We'll have to do lunch sometime—call my assistant to arrange a date." I really have to run, darling, but we simply have to do lunch sometime! I'd love to catch up with you soon.
See also: have, lunch, sometime, we
Farlex Dictionary of Idioms.

We('ll) have to do lunch sometime,

 and Let's do lunch (sometime).
We must have lunch together sometime. (A vague statement that may lead to lunch plans.) Rachel: Nice to talk to you, Tom. We have to do lunch sometime. Tom: Yes, good to see you. I'll give you a ring. Tom: Can't talk to you now. Catch you later. Mary: We'll have to do lunch sometime. John: Good to see you, Tom. Tom: Right. Let's do lunch sometime. John: Good idea. I'll call you. Mary: Catch you later. Sue: Sure. Let's do lunch. Mary: Okay. Call me. Bye.
See also: have, lunch, sometime, we
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
See also:
  • we must do lunch sometime
  • Let’s do lunch
  • Let’s do lunch sometime
  • Let’s do the lunch thing
  • let's do lunch (sometime)
  • let's do the lunch thing
  • read it and weep
  • read 'em and weep
  • not in my back yard
  • Not in my backyard!