How to display a 404 error for a page that is not translated

How can I redirect an untranslated page to a 404 error?

languages:
  supported:
    - en
    - cs
    - sk
  default_lang: null
  include_default_lang: false
  include_default_lang_file_extension: true
  translations: true
  translations_fallback: false
  session_store_active: false
  http_accept_language: false
  override_locale: false
  pages_fallback_only: false

Is there any way to get a 404 error if the page isn't translated in that language? (although it is in supported languages)
For example, I have /en/welcome only in English language, so when i enter the url /cs/welcome, I want to display an error and not page in the default English.
Is it possible to set this in the administration?

Thank you very much for any help