No can do!

no can do

I can't do that; that cannot be done; that's not possible. A: "I need the keys into the storage closet." B: "No can do. I'm under strict orders not to lend them to anyone until we figure out who's been stealing supplies." A: "Why don't we just reset the servers?" B: "No can do! We have so much connected to the live servers that resetting them would cause a system-wide meltdown."
See also: can, no
Farlex Dictionary of Idioms.

No can do!

sent. It can’t be done.; I can’t do it. Lend you $200? No can do!
See also: can, no
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions
See also:
  • not for a second
  • not for a minute
  • not for a moment
  • aint
  • ain't
  • not for a instant
  • not for a/one minute/moment/second/instant
  • by no means
  • not by any means
  • (I) hope not