Israeli Prime Minster Benjamin Netanyahu says U.S. and Israeli warnings of a military strike have not convinced Iran that they are “serious about stopping” Tehran from developing nuclear weapons.

“Right now the Iranian regime believes that the international community does not have the will to stop its nuclear program. This must change and it must change quickly, because time to resolve this issue peacefully is running out.''

U.S. Defense Secretary Leon Panetta met with the Israeli prime minister in Jerusalem Wednesday after speaking earlier with Israeli Defense Minister Ehud Barak in Tel Aviv. In his talks, Panetta reiterated U.S. policy that “all options,” including military action, are on the table to stop Iran from developing an atomic weapon.

“It is my responsibility as secretary of defense to provide the president with a full range of options, including military options, should diplomacy fail. President Obama has made clear that preventing a nuclear-armed Iran is a top national security priority [for] the United States and that all options, all options are on the table.”

Barak expressed doubt that sanctions and diplomacy will lead Iran to halt its nuclear activities.

“We see both the sanctions and diplomacy going further than in the past. They have clearly a certain impact. But to tell the truth, we in Israel see the probability that it will lead the ayatollahs to gather around the table, look at each other's eyes and tell each other that 'the game is over, we have to give up our nuclear military program,' the probability of this happening is very, extremely low, and it's important to notice that while sanctions are taking place and diplomacy takes place, it takes time, and in the meantime, the Iranians are keeping enriching daily uranium.”

Panetta's visit also includes talks with President Shimon Peres.

The U.S. defense chief has denied reports that talks with Israeli leaders would cover potential plans for a preemptive attack on Iran's nuclear facilities.

Panetta arrived in Israel from Egypt, where he met with newly elected President Mohamed Morsi. He described Mr. Morsi as being “his own man,” despite his ties to the conservative Muslim Brotherhood, and said the Egyptian leader is committed to democratic reforms.

Panetta called U.S.-Egyptian military relations an anchor of regional stability for 30 years.