As only recently the MB said they would tear up the peace treaty with Israel. A deal with the PA would face similar pressure due to the rule Egypt plays and the MB Hamas connection. What has not been said while all focus on Israel security concerns is that the PA are in a tight spot, with the Wikileaks and then to lose support of the moderates in Egypt. A wider regional agreement comes from an agreement with the PA. Mind you it is not over yet Mubarak has not stepped down and is not going too.
from the article: Egypt send tanks into Cairo square as 20,000 protesters gather