King Abdullah II warned on Wednesday that his country could never again serve as a "substitute homeland" for Palestinians, in a clear sign that Jordan feared a destabilizing flood of refugees if Israel unilaterally redraws its borders. Abdullah began a quick visit to Saudi Arabia for consultations ahead of his meeting Thursday with Prime Minister Ehud Olmert on reviving the Israeli-Palestinian peace process. His sharp warning underlined the king's opposition to Olmert's plans to draw a West Bank border if negotiations with the Palestinians fail. Before his departure, the king told Jordanian security cadets that if there "is anyone who believes that it is possible to settle the Palestinian issue at the expense of Jordan, he should know that Jordan will never be a substitute homeland for anybody." "The Palestinians' homeland and their state should be on Palestinian soil, and nowhere else," he said. Abdullah's comments also aimed to lay down the line for the Palestinians. In September 1970, the Palestine Liberation Organization tried to overthrow Jordan's Hashemite monarchy by setting up a Palestinian government in the kingdom - a move that led to the bloody "Black September" civil war as Jordan evicted the PLO from its territory. In a sign of the vigorous behind the scenes diplomacy at work, Abdullah also praised the proposal by Palestinian President Mahmoud Abbas to hold a referendum among Palestinians on the prisoner's document, which recognizes the 1967 borders. Olmert was scheduled to arrive in Jordan Thursday on his second trip to an Arab country since taking office in May. Both Olmert and Abdullah traveled to Washington in recent days. In an interview with Yediot Ahronot, Abdullah told the Israeli public that he was "definitely concerned" about Olmert's plan. "A unilateral step by Israel would raise question marks and a sense of insecurity not only among the Palestinians, but among all the partners of peace in the region," he said. Abdullah told Yediot Ahranot that the referendum was "a good opportunity to reach a consensus" among the Palestinians, saying "ultimately we need Palestinian unity in order to promote peace initiatives." The Jordanian king also implicitly lashed out at Iran, saying it was trying to spread its radical version of political Islam across the Middle East. "It is clear that there are parties and states who seek to benefit from this state of affairs. Some seek to settle their problems at the expense of neighboring countries," he said. "Others want to ignite this situation and spread chaos and destruction in more than one place, to enhance their influence and control over the whole region," he added.