Rival Palestinian factions have so far failed to overcome obstacles in reconciliation talks which they hope will lead to a unified governing body for the Gaza Strip and the West Bank, officials said on Friday. President Mahmoud Abbas's Fatah movement has insisted during Egyptian-hosted talks taking place in Cairo that Hamas must “abide” by existing peace agreements signed with Israel but Hamas has refused to make such a commitment. Hamas proposed using the word “respect” instead of “abide” but this falls short of satisfying the United States, Israel and the West, who want the group to endorse peaceful settlements with Israel. The agreements and commitments with Israel were signed by the Palestine Liberation Organization (PLO), which is currently headed by Abbas. Hamas, which won a parliamentary election three years ago, controls the Gaza. Israel, the United States and Western countries have refused to recognize Hamas's control of Gaza. Israel, which has imposed a blockade on the coastal territory, has demanded an end to Hamas rule before it considers easing its restrictions. The Fatah-Hamas dispute was one of the points that prompted intervention of Egyptian intelligence chief Omar Suleiman who met leaders of the two groups late on Thursday to try to narrow differences, officials said. “It remained a point of disagreement,” said Fatah's delegate to the talks, Ashraf Goma. Abbas, talking to reporters in the West Bank town of Ramallah, admitted that negotiations “had encountered difficulties.” “It requires effort and genuine will in order to reach national reconciliation. We don't want to talk about obstacles, we hope the talks will succeed,” Abbas said. Hamas delegate Fawzi Barhoum told Reuters from Cairo that differences remained. “We have not yet agreed to the agenda of the new government and there are obstacles that needed to be removed to reach a balanced formula,” he said. Fatah and Hamas formed a short-lived unity government in 2007, whose platform said it would “respect” the PLO's previous commitments. But it was not enough to prompt a lifting of an international embargo on the coastal territory. Hamas, whose founding charter calls for Israel's destruction, has said it could accept a Palestinian state in lands Israel captured. Hamas has insisted on the right to all of Palestine, including what is now Israel, but has said that it could commit to a long-term truce lasting 15-20 years. Another obstacle Hamas says has “overshadowed” the working of five factional committees assigned to reach a deal is the continued detention of hundreds of Hamas supporters in the Israeli-occupied West Bank by Fatah security services. Security services loyal to Abbas, who deny holding anyone on political grounds, said they freed 45 Hamas supporters on Thursday. A Hamas official confirmed 30 releases but said eight more supporters were detained on Thursday night. “The issue has become the biggest obstacle facing chances of success of the dialogue and it laid its shadow over the entire discussion. We will never skip over this point,” Barhoum said.