Israel's army is capable of attacking Iran on its own without foreign support, Chief of Staff Benny Gantz told public radio on the 65th anniversary of the Jewish state's foundation.
Asked in an interview if Israel's military could wage attacks "alone" -- without the support of countries such as the United States -- against the Islamic republic, Gantz replied, "Yes, absolutely."
"We have our plans and forecasts... if the time comes we'll decide" on whether to take military action against Tehran, he said.
Gantz's comments echoed statements earlier this month by Prime Minister Benjamin Netanyahu, who said Israel would "at no stage... abandon our fate into the hands of other countries, even our best friends."
Israel believes the Islamic republic, which has issued numerous bellicose statements against the Jewish state, is working to achieve military nuclear capabilities. It has not ruled out a military strike to prevent this happening.
Last month Iran's supreme leader Ayatollah Ali Khamenei said his country would "annihilate" the Israeli cities of Tel Aviv and Haifa if it comes under attack by the Jewish state.
Iran denies it is developing an atomic bomb and says it needs its nuclear programme for peaceful medical and energy purposes.
Israel is widely believed to be the Middle East's sole nuclear-armed state, albeit undeclared.
In a separate interview on Tuesday, Gantz said the possibility of an Israeli strike on Iran was not imminent, and that sanctions imposed by the international community should be given priority to stop Tehran's nuclear drive.
"Iran has the means to obtain nuclear capability before the end of the year, but this does not mean it'll get there," he told news website YNet, adding that "sanctions, isolation and continued pressure" on Tehran must intensify.
Iran is estimated to have lost billions of dollars in oil sales and the value of its currency has plummeted.
An independent February report said a fall in pharmaceutical exports to Iran was also causing harm and was undeniably triggered by international sanctions.
US President Barack Obama said in March that Iran was still more than a year away from developing a nuclear weapon.
In a third interview, with Israeli military radio, Gantz also warned of the security threat posed by neighbouring Syria's civil war.
"The rebels are for now engaged in combat against the army of President Bashar al-Assad," he said.
"But it's clear there will be a second war, possibly between (current opponents of Assad), or possibly directed at us. I think it'll be both at the same time," he said.
Mortar rounds and small-arms fire from inside Syria landed in Israeli-controlled territory in the Golan Heights earlier this month, with the Israeli army responding with tank fire.