US Ambassador to Israel Dan Shapiro on Thursday insisted the United States and Israel are “coordinated” on steps being taken to confront Iran’s nuclear program.

Shapiro’s remarks came just days after the most recent public flare up between officials in Jerusalem and Washington over a potential military strike on Iran’s nuclear facilities.

On Tuesday, Prime Minister Binyamin Netanyahu charged US chairman of the Joint Chiefs of Staff General Martin Dempsey with being “unwilling to aid” Israel against Iran.

Dempsey had asserted a pre-emptive strike on Iran’s nuclear facilities would be “destabilizing” for peace talks and “not prudent.”

Dempsey added that a US-led attack would not resolve the matter and said that immediate strikes “wouldn’t achieve their long-term objectives.”

Shapiro, however, said both countries were hoping the economic sanctions in place would persuade Iran to abandon its nuclear ambitions, and they were having a “significant effect” but had not yet achieved their goal.

“It is clear that Iran is under significant economic strain … (but the sanctions have) not yet achieved the goal, which is to get that nuclear program stopped … for both us and for Israel this is the preferred strategy, to achieve that all-important objective,” he told US-Jewish community leaders.

Shapiro added: “It’s also true, as the president has said … we are coordinated with our Israeli partners … that other options, all other options, are on the table to achieve that goal … the necessary planning has been done to ensure that those options are actually available if at any time they become necessary.”

Netanyahu last Wednesday publicly said sanctions are “not working,” a sentiment supported by US Defense Intelligence Agency chief Lt. Gen. Ronald Burgess in testimony given to US lawmakers.

Israel’s premier is widely believed to back Defense Minister Ehud Barak who believes a pre-emptive military strike on Iran’s nuclear program must be made before Tehran enters “the immunity zone.”

Barak’s so-called “immunity zone” is a theoretical point of no return after which Iran’s nuclear program would be so diffuse and well protected that an Israeli strike could not sufficiently delay Iran from obtaining nuclear weapons.

Analysts note that the point of an Israeli strike may not be to completely eliminate Iran’s nuclear program, but to delay it long enough for far-reaching sanctions to have the desired effect.

The International Atomic Energy Association published a 13-page report in November 2011 charging Iran with seeking nuclear technology of a military nation and systemically obstructing international inspectors.

The report, citing intelligence reports from ten different member states, buttressed charges from Israel, the United States, its Western allies, and Gulf Arab nations that Iran is secretly pursuing nuclear weapons.

Irrespective of Shapiro’s reassurances of mutual coordination, this week’s row over Iran was only the latest sign of deep divisions between Jerusalem and Washington over Iran.

In recent months US officials have leaked not only secret visits by Mossad chief Tamir Pardo to discuss a potential military strike on Iran, but Israel’s theoretical time-table for launching such a strike.

Officials in the Obama administration also took the unusual step of siding with Iran and charging Israel’s Mossad with backing a People’s Mujahadeen of Iran assassination campaign targeting Iranian nuclear scientists.