A pre-condition attempts to determine (part of) the outcome of negotiations before they are held. If Israel DOES freeze construction of new settlements, this does not determine the outcome of borders etc., so I wouldn't call the Palestinian demand a pre-condition. If Israel does NOT freeze construction, this DOES change the outcome of the talks. Such a freeze is therefore not a "pre-condition" to the talks, but a necessary condition for the talks to be held. Netanyahu no doubt is clever enough to understand this, but the rest of the Israeli public may not be. Even some members of the Israeli government seem to get confused by this word game.
Libya rival government calls for regional conference to tackle migrant influx (Reuters)
from the article: Israel says 'ready for talks on all core issues' with Palestinians