official confirmation

noun phrase

1. A formal statement or notice from an authorized person or organization confirming that something is true, approved, or arranged.

   B2

   usually uncountable; can be countable with “an”

   • "We are waiting for official confirmation of the result."B1
   • "The company issued official confirmation that the new policy would take effect in July."B2
   • "Without official confirmation, the report should be treated as unverified."C1