An unofficial truce between Israel and Hamas will hold as long as Egyptian mediation continues, a Palestinian official close to Egyptian-sponsored talks said on Saturday, according to Reuters. Israeli Prime Minister Ehud Olmert ordered a "unilateral" end to a devastating 22-day military attack on the coastal territory last Saturday, and Hamas and other Gaza Palestinian factions called their own halt hours later. Nothing was signed and there is as yet no official ceasefire between them. But the Palestinian official, speaking on condition of anonymity, told Reuters he did not expect Hamas or any other faction to call off the truce, since Egyptian leaders were due to meet Hamas officials in Cairo on Sunday to discuss conditions for a durable ceasefire. Hamas official Ayman Taha, a member of the Gaza three-man delegation, said officials from the group's exiled leadership in Syria were also due in Egypt later on Saturday for talks. Hamas said any new deal with Israel must ensure the opening of all border crossings with the Jewish state, which maintains a tight blockade of Gaza. Hamas also demands the reopening of the Rafah border crossing with Egypt, the Palestinians' only window to the outside world that does not go through Israel, and the lifting of the economic blockade. "We are here to discuss how a ceasefire can become durable," Taha told Reuters by telephone from Cairo. Israel on Friday dismissed international calls for a full reopening of border crossings with the Gaza Strip, leaving the shaky ceasefire in question and casting doubts on the viability of post-war reconstruction for Gaza's 1.5 million people. Hamas leaders reject opening the Rafah crossing under conditions set by a 2005 U.S.-brokered agreement that would turn over control of security to the Palestinian Authority together with European monitors, to ensure no weapons are smuggled in. Hamas insists on playing a significant role in the Rafah administration, but the official said it was willing to accept the presence of members of Abbas's presidential guards, with a special arrangement he did not disclose. Leaders of the group have in the past said they could also accept European monitors on certain conditions that does not allow the international observers to have a say over the operation of the crossing. Hamas officials also said that the captured Israeli soldier Gilad Shalit would only be released in exchange for prisoners being held in Israeli jails, a demand they have made since the capture.