Following conciliatory signals from Palestinian Authority Chairman Mahmoud Abbas to Hamas, Prime Minister Ehud Olmert's office warned Wednesday night that any Fatah-Hamas unification would lead to a breakdown in the diplomatic process with the reconstituted PA. Speaking to reporters after a meeting in Ramallah with Japanese Foreign Minister Taro Aso, Abbas - for the first time since Hamas's takeover of Gaza in June - seemed to soften his stance toward the Islamist movement, calling on it to "return to national unity." Abbas's remarks were interpreted by Palestinians as an appeal to Hamas to resume talks with his Fatah faction. Hamas immediately welcomed Abbas's statements and invited him to talk to the movement's leaders in the Gaza Strip. "The split that happened [between the West Bank and the Gaza Strip] as a result of Hamas's coup is temporary and will be removed," Abbas said. "The Palestinian people are opposed to this separation because we want a united and independent Palestinian state." Abbas said he would continue to work toward reuniting the Palestinians. "We will also continue to support our people in the Gaza Strip, because this is our responsibility," he said. Prime Minister Ehud Olmert's office said in a statement that any Fatah-Hamas unification would lead to a breakdown of the diplomatic process, and that the PA chairman was "well aware" of this position. Olmert, according to his office, told Abbas as much at their meeting last week in Jericho, and government officials have said that the progress Israel had made with the PA over the last two months would end if Hamas once again joined the government. Israeli officials quoted Abbas as telling Olmert at their meeting that he would not conduct a dialogue with Hamas, despite pressure from a number of Arab countries to do so. In another sign of rapprochement between Hamas and Fatah, the Fatah-controlled PA security forces in Bethlehem released nine Hamas members on Wednesday who were arrested last month on suspicion of trying to establish an armed Hamas group in the West Bank. Farid al-Atrash, a lawyer representing the Hamas detainees, said a PA court ordered their release, and that the court's decision was endorsed by PA Prime Minister Salaam Fayad. A Hamas spokesman in Gaza City welcomed Abbas's remarks as "positive" and expressed hope that the PA chairman would visit the Gaza Strip for talks with Hamas leaders on ways of resolving the crisis. Abbas's conciliatory remarks come amid reports that Fatah and Hamas are holding secret talks. Sources close to Hamas said several Arab and Islamic countries were involved in mediation efforts. The sources said the Hamas leadership in Syria was conducting secret negotiations with some senior Fatah leaders over ways of ending the dispute before Ramadan, which begins in mid-September. Meanwhile, Abbas, at the press conference with Aso, thanked Japan for providing the Palestinians with $20 million in financial aid. The Japanese minister announced that his government was planning to give half of the sum directly to the PA and the other half as humanitarian aid. Following the meeting in Ramallah, Aso went to Jericho for a meeting with Foreign Minister Tzipi Livni, PA negotiator Saeb Erekat and Jordanian Foreign Minister Abdelelah al-Khatib to discuss a proposed joint economic project. At the meeting, heavy on symbolism but short on substance, the leaders agreed to hold a meeting of experts in October to push the project forward. The Japanese-initiated plan is to set up an agro-industrial park in the Jordan Valley, with goods and products from that park to be transported to a Jordanian distribution center for shipment to the rest of the Arab world. During the meeting at the city's Intercontinental Hotel, Livni said the park would contribute to the development of an "independent and viable Palestinian economy." She said that this project could open a potentially huge market for the PA in the Arab world. Erekat, meanwhile, told reporters after the meeting: "This is not a substitute for a meaningful peace process between the two parties that will lead to a two-state solution."