Sorry, Kobi, I have sympathy for Shalit, but his situation is not relevant to my point. The fact is that by imprisoning a majority of the Hamas members of the Palestinian Parliament Israel has invalidated any vote the Parliament might make in favour of a treaty. Hamas would have an open-and-shut case later that the vote was invalid (in fact I think the Parliament is even inquorate), and so they could renounce the treaty. So Israel does indeed have no partner who can sign anything.
EU's Mogherini in Tehran to talk nuclear deal, regional issues (Reuters)
from the article: Knesset give preliminary okay to bill requiring 80 MKs to divide J'lem