WASHINGTON—Israeli officials say they won't warn the U.S. if they decide to launch a pre-emptive strike against Iranian nuclear facilities, according to one U.S. intelligence official familiar with the discussions. The pronouncement, delivered in a series of private, top-level conversations, sets a tense tone ahead of meetings in the coming days at the White House and Capitol Hill.

Israeli officials said that if they eventually decide a strike is necessary, they would keep the Americans in the dark to decrease the likelihood that the U.S. would be held responsible for failing to stop Israel's potential attack. The U.S. has been working with the Israelis for months to persuade them that an attack would be only a temporary setback to Iran's nuclear program.

Israeli Prime Minister Benjamin Netanyahu and Defense Minister Ehud Barak delivered the message to a series of top-level U.S. visitors to the country, including the chairman of the Joint Chiefs of Staff, the White House national security adviser and the director of national intelligence, and top U.S. lawmakers, all trying to close the trust gap between Israel and the U.S. over how to deal with Iran's nuclear ambitions.

Netanyahu delivered the same message to all the Americans who have traveled to Israel for talks, the U.S. official said.

The official spoke on condition of anonymity to discuss sensitive strategic negotiations.

The White House did not respond to requests for comment, and the Pentagon and Office of Director of National Intelligence declined to comment, as did the Israeli Embassy.

Iran claims its nuclear program is for peaceful purposes, but the International Atomic Energy Agency has raised alarms that its uranium enrichment program might be a precursor to building nuclear weapons. The US has said it does not know whether the government has decided to weaponize its nuclear material and put it on a missile or other delivery device.

The secret warning is likely to worry US officials and begin the high level meetings with Israel and the US far apart on how to handle Iran.

But the apparent decision to keep the U.S. in the dark also stems from Israel's frustration with the White House. After a visit by National Security Adviser Tom Donilon in particular, they became convinced the Americans would neither take military action, nor go along with unilateral action by Israel against Iran. The Israelis concluded they would have to conduct a strike unilaterally -- a point they are likely to hammer home in a series of meetings over the next two weeks in Washington, the official said.

Barak will meet with top administration and congressional officials during his visit. Netanyahu arrives in Washington for meetings with President Barack Obama next week.