The most common and most likely answer to this crossword clue is the 2 plus 3 plus 5 plus 4 plus 3 letter word IF YOU CAN’T BEAT ‘EM
I've seen this crossword clue in Financial Times
I
F
Y
O
U
C
A
N
â
€
™
T
B
E
A
T
â
€
˜
E
M
Buddy explains!
The straight part
We know that "Statement of resignation" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case statement of resignation = if you can’t beat ‘em.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.