Monkey and donkey close to bridge creating gridlock (7)
I believe the answer is:
impasse
'gridlock' is the definition.
(I've seen this before)
'monkey and donkey close to bridge' is the wordplay.
'monkey' becomes 'imp' (synonyms).
'and' means one lot of letters go next to another.
'donkey' becomes 'ass' (ass is a term for a donkey).
'close to' indicates one should take the final letters (the close of something is the end).
The last letter of 'bridge' is 'e'.
'imp'+'ass'+'e'='IMPASSE'
'creating' acts as a link.
(Other definitions for impasse that I've seen before include "Dead end" , "nothing can be done" , "Stand-off, stalemate" , "cul-de-sac" , "Unpromising situation" .)