The political situation between Israel and Palestine is tumultuous at best. However, there needs to be diplomacy between the two regions to reach a mutually benefiting solution. In order for diplomacy there must be a freeze on the developments in Palestinian territories. This is a sign of good faith and a better way for diplomacy to work.
No, a ban on Israeli settlements in Palestinian territories is not justified, because the land is properly Israel's in the first place. Israel was promised the land after World War Two. Israel's live in peace, and only respond to aggression from Palestine defensively. It is unfair to block Israeli settlements, because the Israeli's only want to live in peace.