The differences between Israel and the U.S. on whether to take action against the Ayatollah regime over its nuclear weapons program have deepened. The U.S. still believes that Iran is not on the verge of producing a nuclear weapon and that Tehran has not made a decision to pursue one, U.S. officials said on Thursday.

Their comments came after Israeli media reports claimed U.S. President Barack Obama had received a new National Intelligence Estimate saying Iran had made significant and surprising progress toward military nuclear capability.

The new National Intelligence Estimate report on the Iranian nuclear program is very similar to Israeli assessments on the matter, and the perturbing nature of the report highlights the disparity between Prime Minister Benjamin Netanyahu's position to that of President Obama.

Later, Defense Minister Ehud Barak suggested that the new U.S. report, which he acknowledged might be something other than a National Intelligence Estimate, "transforms the Iranian situation into an even more urgent one."

But U.S. National Security Council Spokesman Tommy Vietor disputed the Israeli reports, saying the U.S. intelligence assessment of Iran's nuclear activities had not changed since intelligence officials delivered testimony to Congress on the issue earlier this year.

"We believe that there is time and space to continue to pursue a diplomatic path, backed by growing international pressure on the Iranian government," Vietor said. "We continue to assess that Iran is not on the verge of achieving a nuclear weapon."

The alleged U.S. intelligence report points to a significant increase in Iranian efforts to advance its nuclear program. Iran's amplified efforts, which have been especially noticeable over the past four months, include uranium enrichment activities to higher levels and along all parameters. In regards to U.S. and Israeli intelligence and security assessments on the matter, the two countries have reached common ground and there is no longer a question that Iran's nuclear program is designed for military purposes. There is also no dissent regarding the amount of fissile material in Iran's possession or how it is being enriched.

The primary difference between the U.S. and Israel is on the diplomatic front. The two countries are at odds over what constitutes the red line that if crossed by Tehran would lead to military action against Iran.

During his recent visit to Israel, U.S. Secretary of Defense Leon Panetta outlined a very problematic red line as far as Israel is concerned. According to Panetta, the red line for the U.S. is an Iranian decision to make a bomb.

Israel's red line is preventing Iran from becoming a "threshold state" — a country that is capable of making a nuclear weapon but has yet to decide to do so.

There are several threshold states in the world, like Germany and Japan for example. Israel's political leadership believes that the U.S. is sees Iran the same as moderate threshold countries, which act as reasonable, rational states.

Jerusalem contends that a nuclear threshold state can build a bomb in a short period of time, and that countries like Pakistan and North Korea were able to conceal their progress. At such a point, according to Israel, the decision to try and stop them comes with much greater risk.

U.S. officials would not directly comment on whether there was a new National Intelligence Estimate on Iran, which is a compilation of views of the various U.S. intelligence agencies.

The last formal NIE on Iran in 2007, partially made public by the administration of President George W. Bush, became highly controversial because it said Tehran had halted nuclear weaponization work in 2003, although other aspects of the overall program continued. A later update to that report retained that central assessment, sources have previously said.

James Clapper, U.S. director of national intelligence, said in congressional testimony in January: "We assess Iran is keeping open the option to develop nuclear weapons, in part by developing various nuclear capabilities that better position it to produce such weapons, should it choose to do so. We do not know, however, if Iran will eventually decide to build nuclear weapons."

Barak told Israel Radio: "There probably really is such an American intelligence report — I don't know if it is an NIE one — making its way around senior offices (in Washington)."

"As far as we know it brings the American assessment much closer to ours ... it makes the Iranian issue even more urgent and (shows it is) less clear and certain that we will know everything in time about their steady progress toward military nuclear capability."

In the meantime, the Iranians have not succumbed to sanctions and the Americans have yet to announce that negotiations with Tehran are a failure. The Ayatollah regime is under the impression that the U.S. has no intention of armed conflict and that they have time to operate "quietly" until the U.S. elections in November.

Sign up for our daily newsletter>>