in no uncertain terms
US /ɪn noʊ ʌnˈsɜrtn tɜrmz/
UK /ɪn noʊ ʌnˈsɜrtn tɜrmz/

1.
clearly and directly, leaving no doubt
:
•
She told him in no uncertain terms that she would not tolerate his behavior.
•
The manager explained in no uncertain terms what was expected of the team.