The US Secretary of State Antony Blinken has urged Hamas to accept Israel's latest proposal for a Gaza truce and hostage release deal, calling it “extraordinarily generous”. It comes as a Hamas delegation left Cairo late on Monday following extensive discussions with Egyptian brokers.  The terms of the draft deal were not made public. But Israeli media said Israel softened its position, now seeking the release of 33 hostages, down from 40, in return for the release of some 900 Palestinian prisoners.  Hamas is believed to hold around 100 Israelis in the Gaza Strip.  The Palestinian militant group will "return with a written response to the truce proposal," according to Egyptian security sources. “Hamas has before it a proposal that is extraordinarily, extraordinarily generous on the part of Israel, and at this moment, the only thing standing between the people of Gaza and ceasefire is Hamas,” Blinken said at a World Economic Forum gathering in Riyadh. “They have to decide, and they have to decide quickly. So, we're looking to that, and I'm hopeful that they will make the right decision and we can have a fundamental change in the dynamic,” he added. An Israeli delegation, composed of security officials, will depart on Tuesday to discuss the deal with the Egyptian brokers, Israeli media report. Hamas has so far baulked at a series of offers negotiated by Egypt, Qatar and the United States and agreed to by Israel. Even without a deal, Blinken said it was critical to improve conditions in Gaza now. “We're also not waiting on a ceasefire to take the necessary steps to meet the needs of civilians in Gaza,” Blinken told Gulf Cooperation Council foreign ministers earlier Monday.  He commented after arriving in Saudi Arabia for the first stop of his Middle East tour, which includes trips to Jordan and Israel on Tuesday and Wednesday. One question is whether that will be enough to overcome Hamas' concerns over the ceasefire's second phase. Hamas has demanded assurances that an eventual release of all hostages will bring a complete end to Israel's nearly seven-month assault in Gaza and a withdrawal of its troops from the devastated territory.  Israel has offered only an extended pause, vowing to resume its offensive once it is over.  The issue has repeatedly obstructed efforts by US, Egyptian and Qatari mediators during months of talks. Hamas said on Monday in a statement that ensuring a permanent ceasefire is a fundamental cornerstone for moving towards the details of negotiations and the success of the agreement with Israel. Abdul Latif al-Qanou, a spokesman for Hamas, stressed the necessity of fulfilling the demands of the Palestinian people, including "a permanent ceasefire, withdrawal of forces from the Gaza Strip, and the return of refugees." Under the mediation of Egypt, Israel proposed the latest ceasefire agreement, warning that now is the "last chance" for a truce deal before the Israeli army launches a ground operation in the southern Gaza city of Rafah where more than 1.5 million Palestinians are taking refuge.