The most common and most likely answer to this crossword clue is the 6 plus 10 letter word CHARGE D’AFFAIRES
I've seen this crossword clue in The Guardian
C
H
A
R
G
E
D
â
€
™
A
F
F
A
I
R
E
S
More clues leading to the result CHARGE D’AFFAIRES
Buddy explains!
The straight part
We know that "Official" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case official = charge d’affaires.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.