Translate the following English sentence to French:
"Now, however, it would seem that the rest, the remaining 20%, are so problematic, that time is passing by and the talks have already ended in deadlock on many occasions."
On a pourtant maintenant l' impression que le reste, les vingt derniers pour cent, est si problématique que le temps passe et que les négociations ont déjà plusieurs fois débouché sur une impasse.