In a blistering attack on the Israeli government’s handling of relations between Jerusalem and Washington, former prime minister Ehud Olmert accused Benjamin Netanyahu, Israel’s current leader, of trying to undermine President Barack Obama’s reelection chances and spitting in his face.

Olmert made the remarks in an hour-long investigative news program, which aired on Monday and depicted Israeli efforts over the past decade to prevent Iran from developing nuclear weapons.

Among the program’s revelations: in 2010, Netanyahu ordered his military to go on high alert in preparation for an attack against Iran, but backed off under pressure from Israel’s army and intelligence chiefs.

Olmert, who left the prime minister’s office in 2009 under a cloud of corruption charges, is weighing a return to politics ahead of Israel’s Jan. 22 election. His rebuke seemed at least partially motivated by the possibility that the two men may soon become rivals in the race for the country’s top political job.

But it also reflected a broader criticism here against Netanyahu, who has butted heads with Obama over settlement expansion and threatened to order a unilateral Israeli strike against Iran if the U.S. fails to stop Tehran’s uranium enrichment.

Olmert said the ultimatum was unseemly given Israel’s reliance on U.S. military aid and weapons supplies. “What’s all this talk that we alone will determine our fate and we won’t take anyone else into consideration,” he said on the eve of the American presidential election, in an interview with Fact, the news program, which airs on Israeli Channel Two and is hosted by the journalist Ilana Dayan.

“Someone needs to explain to me what planes exactly we intend to use to attack, if indeed we decide to attack alone, against the wishes of others. Planes that we manufactured here? What bombs will we use to attack? Bombs that we manufactured? What special technologies will we use to wage our attack?”

“And if we have run out of something, who will we approach to get more? The person in whose face we’re now spitting? The person we’re trying with all our might to make sure won’t be the president of the United States?”

Israel’s strong ties with the U.S. are seen here as one of the country’s most important strategic assets. Israeli voters have been known to punish leaders who jeopardize the relationship.

But Netanyahu frames the Iranian nuclear program as an existential threat to Israel and puts efforts to abolish it above almost everything else. In a short interview that aired as part of the segment, he defended Israel’s right to attack Iran without American approval.

Olmert, who left the prime minister’s office in 2009 under a cloud of corruption charges, is weighing a return to politics ahead of Israel’s Jan. 22 election.

“If someone sits here as the prime minister of Israel and he can’t take action on matters that are cardinal to the existence of this country, its future, and its security, and he is totally dependent on receiving approval from others, then he is not worthy of leading,” Netanyahu said.

“If what I just heard is that on this matter, which threatens our very existence, we should just say, we should just hand the keys over to the Americans and tell them, ‘You decide whether or not to destroy this project, which threatens our very existence,’ well, that’s one possible approach, but it’s not my approach,” he said.

Obama has not ruled out an American strike on Iran, but says there’s still time for sanctions and diplomatic pressure to work. His opponent in the American election, Mitt Romney, has at times seemed more willing to countenance a unilateral Israeli strike.

In one of the more unusual aspects of the debate over Iran, Israel’s own military and intelligence brass has appeared to favor Obama’s position over Netanyahu’s. Several retired officials have said so publicly in the past year, including former Mossad chief Meir Dagan, who once described the idea of Israel attacking Iran as “the stupidest thing I ever heard.”

The new program said that Netanyahu and Defense Minister Ehud Barak tried in 2010 to have the military move to a more aggressive posture against Iran, described as “P-plus.” Neither Dayan nor the people she interviewed elaborated on what P-plus meant.

But Dayan said that Dagan, the Mossad chief, and Gabi Ashkenazi, the head of the army at the time, rebuffed the order, telling Netanyahu it was too risky. The two men did not appear on the show and could not be reached for a comment