The most common and most likely answer to this crossword clue is the 7 plus 5 letter word OLYMPIC GAMES
I've seen this crossword clue in The Guardian
O
L
Y
M
P
I
C
G
A
M
E
S
Buddy explains!
The straight part
We know that "this international event" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case this international event = olympic games.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.