He simply doesn't want to do it. His preferred strategy would be to turn aroud and post-hoc "legalize" these "illegal" settlements, but the reaction from the USA would be rather hostile, to say the least. So his next best option is simply to CLAIM that he is working on the solution, and then to sit on his hands, and when anyone calls him on it he says "Gettin' Off My Hands Real Soon Now. Any Moment! Just You Watch Me! Getting Ready! Any Tick Of The Clock!" And then do nothing. And that isn't because he's SCARED, but simply because he doesn't want to do it i.e. he wants those settlements to stay, and he hopes that if he delays long enough then circumstances will change and they WILL be allowed to stay.
Russia: U.S. plan to provide air cover for Syrian rebels undermines Damascus fight on ISIS (Reuters)
from the article: Barak seeks another extension on plan to evacuate outposts