Israel never seems to be able to insert in any of the myriad agreements they have signed with the Pals., either with the U.S., EU or anyone else in the general vicinity, a simple codicil that would clarify the possibility of a "fall back" position for Israel.
It works very simply.
All it would state is that if the Pals. don't do so-and-so or such-and-such, then Israel has the full right to withold, to stop, to prevent, to _______ (fill in any punitive measure) or to revert to any pre-exisiting situation and that the Pals., next time around, have to start their negotiating not from where they left off, as they have always managed to do, but they have to go back and make up lost territory (literally, I would hope).
Is this too much to expect from our brilliant and dashing diplomats?