Senior defense officials have recently been visiting the ultra-Orthodox Shas party's spiritual leader, Rabbi Ovadia Yosef, to discuss a possible Israeli attack on Iran.

Some want the 91-year-old rabbi to support it, others to oppose it. At least one visit, in which the rabbi was briefed on Iran's nuclear program, came at the behest of Prime Minister Benjamin Netanyahu, who is battling for support in the cabinet to strike Iran.

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One of the visitors to Yosef's Jerusalem home was National Security Council head Ya'akov Amidror, accompanied by Interior Minister and Shas political leader Eli Yishai, the Kikar Hashabat website reported.

Yishai reportedly objects to an Israeli attack on Iran in the current circumstances, although he has not made his position clear in public.

It is not known whether Amidror or any of the others succeeded in persuading Yosef. However, on Saturday evening, a day after his meeting with Amidror, Yosef said in his weekly sermon: "You know what situation we're in, there are evil people, Iran, about to destroy us. ... We must pray before [the almighty] with all our heart."

Meanwhile, opposition head MK Shaul Mofaz (Kadima ) on Monday demanded clarifications from Netanyahu over his "intention to lead Israel into war with Iran," saying the costs of such a war would far outweigh its benefits. Mofaz also implied that Netanyahu was opening a rift with the Obama administration in an attempt to influence the November 6 U.S. presidential election, in which the prime minister is widely seen as favoring Republican Mitt Romney.

The Kadima leader wrote Netanyahu a letter asking for an urgent meeting on his plans. According to law, the prime minister must brief the opposition head on a monthly basis.

Mofaz attached a classified document, copies of which were sent to the defense minister, attorney general and chairman of the Knesset's Foreign Affairs and Defense Committee. According to Army Radio, the attached document included a number of questions concerning Israel's preparedness for a war with Iran and relations with the United States.

Mofaz also asked for explanations of the official American position regarding an attack, and the degree of understanding between Washington and Israel in terms of intelligence, operations, the economy and the political arena.

The Kadima chairman added that an Israeli attack on Iran's nuclear facilities would achieve limited results, alongside "loss of life, grave damage to the home front and deep erosion of Israel's political situation.

"Such action is immoral and operationally illogical under the circumstances," he wrote.

Mofaz criticized Netanyahu for his handling of relations with the United States. "What is the real goal behind widening the rift with the United States?" he asked. "Administration officials have clearly demonstrated to you, to the defense minister and to myself the dramatic ramifications of an Israeli operation, which would [constitute] a blunt and illegitimate intervention in internal U.S. political processes in the run-up to the presidential election in November this year," he wrote.

He slammed Netanyahu's response to President Shimon Peres' public objection to an attack. "The unrestrained attack you led against the president over the weekend points to a general loss of senses and control," he wrote.

Also, Gen. Martin Dempsey, chairman of the U.S. Joint Chiefs of Staff, said on Sunday night that the United States and Israel have different interpretations of the same intelligence reports on Iran's nuclear program. Dempsey said Israel viewed the threat posed by Tehran's atomic ambitions with more urgency, as a nuclear-armed Iran could endanger Israel's existence.

Dempsey said he conferred with his Israeli counterpart Lt. Gen. Benny Gantz on a "biweekly" basis. "We compare intelligence, we discuss regional implications. And we've admitted to each other that our clocks are turning at different rates," he said.

Dempsey said the U.S. military felt no pressure from Israel to back possible bombing raids. Speaking to reporters aboard his plane before landing Sunday night at Bagram air base in Afghanistan, Dempsey reiterated his view that any air strikes by Israel would delay but not destroy Iran's disputed nuclear project.

Iranian Defense Minister Brig. Gen. Ahmad Vahidi said on Monday that Israelis were "afraid of their own shadow (and are ) therefore trying to control this disappointing atmosphere by brouhaha and psychological warfare, but should know that propaganda will not resolve their problems."