WASHINGTON (JTA) — Israel’s proposal that Iran totally dismantle its nuclear capacity in exchange for sanctions relief would likely lead to war, a top White House official said.

The official, in a conference call Wednesday with think tanks and advocacy groups sympathetic to the Obama administration’s Iran strategy, outlined the proposal that the major powers will put to Iran at a third round of negotiations in Geneva beginning Thursday.

JTA obtained a recording of the call on condition that it not name the participants or fully quote them.

A think tank participant on the call said Israel’s posture — demanding a total halt to enrichment and the dismantling of all of Iran’s centrifuges — was a path to war.

Agreeing that such reasoning was “sound,” the White House official said that given a choice between “total capitulation” and advancing toward a nuclear weapon, Iran would choose the weapon.

That posture would “close the door on diplomacy” and would “essentially lead to war,” the official said.

The official sounded notes of frustration with Israel’s pushback against the U.S. proposal for a “first step” deal that would exchange some sanctions relief for some rollback of Iran’s nuclear program, saying it would provide Israel with a six-month window to influence the shape of a final deal.

Israeli Prime Minister Benjamin Netanyahu, backed by a number of U.S. lawmakers, wants Iran to totally dismantle its nuclear program and abide by United Nations Security Council resolutions and suspend all its uranium enrichment.

The proposed deal outlined by the official would suspend uranium enrichment for six months at 20 percent, implying that Iran would be able to continue enrichment at 3.5 percent to 5 percent; “address” Iran’s existing stockpiles of 20 percent- and 5 percent-enriched uranium; suspend the development of a heavy water reactor that could produce plutonium; and end the installation and construction of new centrifuges.

The official emphasized that the construction — not just the installation — of new centrifuges would be halted, countering arguments by opponents of an interim deal who say it would buy Iran time to advance its weapons program.

All of this would be verified by intrusive inspections, the official said.

In exchange, the Western powers would release a “fraction” of $100 billion in Iranian frozen funds and end “ancillary” sanctions — the official did not identify them — but keep in place sanctions on Iran’s energy and banking sectors.

The official said the administration was confident that a proposal by a group of Republican senators to attach an amendment adding intensified Iran sanctions to a must-pass defense-funding act would likely not reach the floor of the Democrat-led Senate.

The senators, led by Sen. Mark Kirk (R-Ill.), agree with Netanyahu’s assessment that intensified sanctions at this stage would extract from Iran an agreement to suspend enrichment and dismantle centrifuges.

The White House official said that intensified sanctions would likely not only drive Iran away from the talks but would collapse the international sanctions regime in place by alienating a number of countries now abiding by it.