Release article in Le Monde on problem (7)
I believe the answer is:
unhitch
'release' is the definition.
(I've seen this before)
'article in le monde on problem' is the wordplay.
'article in le monde' becomes 'un' (French indefinite article eg in Le Monde newspaper).
'on' says to put letters next to each other (in a down clue, letters appear on others).
'problem' becomes 'hitch' (hitch can mean a problem or delay).
'un'+'hitch'='UNHITCH'
(Other definitions for unhitch that I've seen before include "Part" , "Separate" , "free?" , "Remove from a harness" , "Release" .)