JERUSALEM - Israeli President Shimon Peres on Thursday came out against any go-it-alone Israeli attack on Iran, saying he trusted U.S. President Barack Obama's pledge to prevent Tehran from producing nuclear weapons.His comments appeared to challenge Prime Minister Benjamin Netanyahu and Defence Minister Ehud Barak, who have both raised the prospect of a unilateral Israeli strike, despite assurances from Washington it will not let Iran get the atomic bomb."I am convinced this is an American interest. I am convinced(Obama) recognises the American interest and he isn't saying this just to keep us happy. I have no doubt about it, after having had talks with him," Peres told Channel Two television. "Now, it's clear to us that we can't do it alone. We can delay (Iran's nuclear programme). It's clear to us we have to proceed together with America. There are questions about coordination and timing, but as serious as the danger is, this time at least we are not alone."A flurry of comments by Israeli officials and media reports over the past week have put financial markets on edge by appearing to suggest an attack could be launched before the U.S. presidential election in November. An unidentified top "decision maker", widely believed to be Barak, told Haaretz newspaper last Friday that Israel "cannot place the responsibility for its security and future even in the hands of its greatest ally", a reference to the United States.Peres said in the interview that he did not believe Israel would launch an attack on Iran before November.As president, Peres, 89, has little political power in Israel. But he has won the respect of many Israelis while serving in the post and his opposition to any unilateral action poses an additional challenge to Netanyahu.A political source close to Netanyahu issued an angry response to Peres' comments shortly after the president's interview was aired."Peres has forgotten what the role of Israel's president is. He has forgotten that he made three major mistakes in regard to Israel's security ... his greatest mistake was in 1981 when he thought bombing the reactor in Iraq was wrong and, to the fortune of Israel's citizens, Prime Minister Begin ignored him," he said, speaking on the condition of anonymity. Israel's prime minister at the time, Menachem Begin, had cautioned that a nuclear-armed Iraq under Saddam Hussein would pose a threat to the existence of the Jewish state and ignored then opposition leader Peres' warnings against the strike.At a news conference in Washington on Tuesday, U.S. Defense Secretary Leon Panetta said it was important that military action be the "last resort", adding that there was still time for sanctions and diplomatic pressure to work."I don't believe they've made a decision as to whether or not they will go in and attack Iran at this time," Panetta said.During a visit to Jerusalem at the start of the month, he made some of his strongest comments yet on curbing Tehran's nuclear project. "We will not allow Iran to develop a nuclear weapon. Period," he told reporters.In parliament on Thursday, Barak said Israeli deliberations on a course of action were continuing."There is a forum of nine (ministers), there is a (security) cabinet, and a decision, when it is required, will be taken by the Israeli government," Barak said."This doesn't mean there aren't differences. The issue is complicated, but the issue is being deliberated," he added.Israeli officials have told Reuters that the prime minister's cabinet was split on the issue, while the top military leadership was believed to be opposed to any mission that did not have full U.S. support."Over the past several months, a wide-ranging and unbridled public relations campaign has been conducted in Israel. Its only aim has been to prepare the ground for premature operational adventures," said opposition leader Shaul Mofaz, who pulled his Kadima party out of the ruling coalition in July.Iran rejects Israeli and Western allegations that its nuclear programme is aimed at producing atomic weapons, and has threatened wide-ranging reprisals if attacked - retaliation that could draw the United States into the conflict.