The United States is ready to "face the challenge on every level" concerning Iran's nuclear drive, Israeli Defence Minister Ehud Barak claimed on Thursday after talks with the deputy US military chief.

"We face a common challenge but the clock is ticking at a different pace for each of us," Barak said after meeting the vice chairman of the US Joint Chiefs of Staff, Admiral James Winnefeld, for talks on Iran.

"We also have our differences; Israel keeps its sovereign right to act independently, and the US understands this. However, there is no doubt about the US readiness to face the challenge on every level," Barak said, according to a statement from his ministry.

Earlier, the defence ministry sent a statement with pictures and a video saying Winnefeld met Barak in his Tel Aviv office, without providing details.

A statement from Winnefeld's office said he was in Israel as part of a previously scheduled counterpart visit with the deputy chief of staff, Major General Yair Naves.

"While there, Admiral Winnefeld will participate in a series of discussions on mil-to-mil (military-to-military) cooperation and mutual defense issues impacting both Israel and the United States," it added.

Initially there was secrecy involving the meeting, with Israeli army radio saying the visit had been kept under wraps because of political sensitivities between Israel and Washington over how to handle Tehran's nuclear programme, which both governments suspect is designed to build atomic weapons.

Tehran insists its programme is completely peaceful, but Israel has warned that a nuclear Iran would pose an existential threat and said it would take all necessary steps to prevent that from happening, including a pre-emptive military strike.

Barak, in the statement released from his office, said talks with Winnefeld focused on "the situation in the region, and of course about the Iran issue."

And he reiterated that "only Israel will take decisions regarding its future and security" in a reference to what plans it may have regarding Iran.

But in remarks apparently aimed at appeasing tensions between allies Israel and the United States over Iran, the defence minister added: "However, the US is our most important ally.

"The intelligence cooperation and the military support are deep and exceptional in scope. I am sure that it will stay this way in any scenario that might happen in the future."

Tensions between the allies have grown in recent weeks amid speculation Israel was mulling an attack on Iran without Washington's approval and pushing the White House to issue a more forceful declaration threatening Iran with potential military action.

Analysts say President Barack Obama's administration is arguing that there is still time to allow sanctions to have an effect on Iran and for further cyber sabotage to disrupt Tehran's nuclear work.

On Monday, Prime Minister Benjamin Netanyahu said the international community must set a "clear red line" in order to avoid a war over Iran's controversial nuclear programme.

"This is a brutal regime that is racing ahead with its nuclear programme because it doesn't see a clear red line from the international community," Netanyahu said at a meeting with Israeli and US servicemen wounded in conflict.