cease and desist

Short definition from Wiktionary

Verb

1. 1
   To stop and not resume an action.

Noun

1. 1
   A written demand that a party stops and does not resume a certain behavior, such as copyright infringement, slander, or libel, threatening legal action if the recipient fails to do so.
2. 2
   An order by a government agency, sanctioned by a court, that one must stop and not resume a certain (usually illegal) behavior.