Fall of a Labour government is not included (4,3)
I believe the answer is:
left out
'is not included' is the definition.
'fall of a labour government' is the wordplay.
I cannot quite understand how this works, but
'of' could be 'o' and 'o' is found in the answer.
'labour' could be 'left' (I've seen this before) and 'left' is found in the answer.
The remaining letters 'ut' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Another definition for left out that I've seen is " Omitted".)