Eagerly accept the French whelp (3,2)
I believe the answer is:
lap up
'eagerly accept' is the definition.
(I've seen this before)
'the french whelp' is the wordplay.
'the french' becomes 'la'.
'whelp' becomes 'pup' ('pup' can be a synonym of 'whelp').
'la'+'pup'='LAP UP'
(Other definitions for lap up that I've seen before include "Delight" , "Drink (water) like a dog" , "motor race by some distance?" , "of future monarch?" , "Take in willingly (with the tongue?)" .)