Israel threatened Monday to pull out of a UN inquiry into a raid on a Turkish flotilla heading for Gaza, after the UN chief said there is no agreement that the panel will refrain from calling Israeli soldiers to testify.Last week Israel agreed to participate in the UN probe into the May 31 raid, when nine pro-Palestinian activists were killed after naval commandos boarded a Turkish vessel aiming to break Israel's blockade on Gaza.RELATED:UN Gaza flotilla panel to hold first meetingLivni: UN flotilla probe will judge IDFOfficials said Israel's agreement was conditional on the panel relying on reports from Israel's own military inquiry, not testimony from soldiers.But at a Monday news conference at UN headquarters on Monday, Secretary-General Ban Ki-moon was asked whether he agreed not to call Israeli soldiers before the panel."No, there was no such agreement behind the scenes," Ban said.In response, the prime minister's Office issued a harsh statement. "Prime Minister Binyamin Netanyahu makes it absolutely clear that Israel will not cooperate with and will not take part in any panel that seeks to interrogate Israeli soldiers," it said. Israel's agreement to join the probe represented a change in its policy of boycotting UN probes. Israel has considered the world body and its committees biased. This time, however, the world outcry against the raid and the spotlight it turned on Israel's three-year blockade on Gaza appeared to give Israel little choice but to cooperate.Israel appointed retired senior diplomat, Yosef Ciechanover to join the UN panel and was preparing for the start of its deliberations on Tuesday when Ban made his remark, throwing plans into turmoil.A senior Israeli official said the advance agreement with Ban was that requests for additional information or clarifications from the panel would be routed through the Israeli representative, and soldiers would not be called to testify."This was and remains a vital condition for Israeli participation in the panel," he said. The official spoke on condition of anonymity because he went beyond the government statement. This appeared to leave the door open for Israel to resume its cooperation if soldiers are exempted from testifying.