Couriers worried about last month's appeals from abroad (4,2,5)

I believe the answer is:

cris de coeur

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'appeals from abroad' is the definition.
I know nothing about this answer so I cannot tell whether it can be defined by this definition.

'couriers worried about last month's' is the wordplay.
'worried' indicates an anagram.
'about' indicates putting letters inside.
'last month' becomes 'dec' (short for December, last month of the year).
'couriers' anagrammed gives 'crisoeur'.
'crisoeur' going around 'dec' is 'CRIS DE COEUR'.

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(Another definition for cris de coeur that I've seen is " Passionate appeals".)

I've seen this clue in The Times.

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