Palestinian factions meeting in Cairo to seal a reconciliation deal between Fatah and Hamas were to hold a second round of talks on Saturday after the failure of initial efforts, delegates said.
The talks are being held under the umbrella of the provisional governing body of the Palestine Liberation Organisation, which is charged with bringing non-members Hamas and Islamic Jihad into the PLO.
A round of discussions on Friday night lasted eight hours.
"The atmosphere was positive but we need another meeting to sort out some interpretations and differences in point of view," Maher al-Taher, head of the Popular Front for the Liberation of Palestine, told reporters.
PLO executive committee member Wassel Abu Yussef said the main differences were over polls to the Palestine National Council (PNC), the PLO's parliament, and over legislative and presidential elections in the Palestinian territories.
"Fatah wants the (transitional non-partisan) government (tasked with organising the elections) formed at the same time as a decree setting the date for elections," Abu Yussef explained.
Signup to our newsletter and follow us on Facebook and Twitter!
"Hamas wants the government to be formed first to end the division before the date of elections is decided."
Also, Fatah and independent figures in the PLO provisional governing body want the same system to apply for the PNC and parliament, whereas Hamas wants proportional representation within the Palestine National Council.
The Islamist movement which rules Gaza wants a breakdown of 75 percent proportional representation for polling in the West Bank and Gaza Strip, and the rest under a one-person, one-vote system.
Palestinian president Mahmoud Abbas, who heads Fatah and the PLO, has convened the conference of all Palestinian organisations in the Egyptian capital, where his party and Hamas signed a reconciliation agreement on April 27, 2011.
Most of its clauses have gone unheeded and deadlines have been postponed.
The PLO provisional governing council met in Cairo for the first time in December 2011. It includes PLO leaders and the heads of groups currently under its umbrella, as well as Hamas, Islamic Jihad and independent personalities.
Hamas last week authorised the Central Elections Commission to start registering voters in the Gaza Strip, removing a major obstacle to reconciliation with Fatah.
The CEC said voter registration will be carried out from February 11 to 18.