The Palestinian Authority should be the sole ruling power in Gaza after the war. This was insisted by Palestinian Prime Minister Mohammed Mustafa, quoted by "Reuters".
He made his statement amid heightened expectations that an agreement to halt the fighting and return Israeli hostages was close.
Who will govern Gaza after the war remains one of the big unanswered questions in the negotiations, which have focused on an immediate ceasefire and the exchange of hostages still held in the enclave for Palestinian prisoners in Israeli jails.
At a news conference in Norway, Mustafa said that pressure must continue to reach an agreement on a ceasefire in Gaza and to allow more humanitarian aid for more than 2 million people facing a severe humanitarian crisis after 15 months of war.
Only the Palestinian Authority is legitimately placed to take over governance in the Gaza Strip after the fighting ends and there should be no attempt to separate Gaza from the occupied West Bank as part of a Palestinian state, he stressed.
"While we await a ceasefire, it is important to emphasize that it will not be acceptable for any entity other than the legitimate Palestinian leadership and government of the State of Palestine to govern the Gaza Strip," Mustafa said.
He pointed out that Norway's recognition last year of a Palestinian state under Palestinian authority was an important step towards a two-state solution, supported in principle by most of the international community.
Israel has rejected any involvement by the Hamas group, which ruled Gaza before the war, but has almost uniformly opposed the rule of the Palestinian Authority - the body created under the Oslo interim peace accords three decades ago, which has limited authority to govern the West Bank.
Israeli officials accuse the Palestinian Authority of supporting attacks on Israel and say that widespread support for Hamas among Palestinians outside Gaza means that any Palestinian state will inevitably be taken over by the Islamist group.
The Palestinian Authority, dominated by the Fatah faction founded by former Palestinian leader Yasser Arafat, also faces opposition from the rival Hamas faction, which ousted it from Gaza in 2007 after a brief civil war.