A long and heated meeting between Palestinian and Israeli negotiators in Jerusalem  ended early Thursday without any signs of bringing both sides back to the negotiating table.Palestinian sources told Ma'an that the nine-hour meeting with US Special Envoy Martin Indyk was attended by PLO negotiator Saeb Erekat, Head of Palestinian intelligence Majid Faraj, and Israeli negotiators Tzipi Livni and Yitzhak Molcho.The sources described the meeting as a "fierce political battle", with Martin Indyk struggling to control heated exchanges between both sides.Erekat reportedly told the Israeli side that "we are here to negotiate in the name of the UN-recognized State of Palestine, not in the name of a Palestinian Authority whose inputs and outputs are controlled by Israel."Israeli negotiators responded by threatening to put "endless" sanctions on the Palestinians , the sources said.During the heated exchanges, US special envoy Martin Indyk reiterated his support for Israel's security.Majid Faraj responded by stressing that the Palestinians were there for "political, not security" talks and to negotiate about Jerusalem as the future capital of an independent Palestinian state .Erekat responded to Israeli threats of sanctions by saying the PLO would go after Israeli officials as "war criminals" in international institutions.U.S. Secretary of State John Kerry phoned President Mahmoud Abbas  on Wednesday as peace talks appeared to have reached an impasse over Israel's refusal to free prisoners. A day earlier, Abbas said he had begun steps to join several UN agencies  and ratify international treaties after Israel failed to release a final group of pre-Oslo Palestinian prisoners.The announcement was a blow to Kerry's frenetic efforts to resolve the dispute over Palestinian prisoners and find a way to extend the fragile peace talks beyond a looming April 29 deadline.In July, the PLO agreed to postpone accession to international bodies in exchange for the release of 104 Palestinians prisoners jailed before the Oslo Accords."Since Israel failed to release the last group of prisoners , the State of Palestine is no longer obliged to postpone its rights to accede to multilateral treaties and conventions," the PLO said in a statement Wednesday."Despite the escalation of oppressive Israeli policies such as the killing of Palestinian civilians, settlement construction, raids on vulnerable communities, arbitrary arrests and detentions, home demolitions and the removal of residency rights, we remained committed to the negotiations process and supported US efforts," it added.