Island starts to cut off regimental fighting units (5)

I believe the answer is:

corfu

'island' is the definition.
(Greek island)

'starts to cut off regimental fighting units' is the wordplay.
'starts to' suggests taking the first letters.
The initial letters of 'cut off regimental fighting units' is 'CORFU'.

(Other definitions for corfu that I've seen before include "Greek holiday island" , "Ionian holiday island" , "Kerkira, Ionian island" , "Greeks here?" , "Popular holiday island off West Greece" .)

I've seen this clue in the Sydney Morning Herald.

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