WASHINGTON – Israeli Prime Minister Benjamin Netanyahu is seizing the bully pulpit of Congress to warn against trusting Iran, even as President Barack Obama’s negotiators continue talking with the Iranians Tuesday in hopes of closing a deal this month.

Netanyahu insists he is privy to emerging details of a potential agreement and is expected to lay out his specific concerns in Tuesday’s speech to a joint meeting of Congress.

The Obama administration has complained that congressional Republicans injected destructive partisanship into the U.S.-Israel alliance by inviting Netanyahu to speak. But the White House played down the controversy in the hours before the address in the House chamber.

Senior adviser Valerie Jarrett called it “a bit of a distraction” but told MSNBC the dispute wouldn’t undermine Obama’s commitment to Israel.

“We share a common goal of ensuring that Iran does not develop nuclear weapons,” Jarrett said, and disagree with Netanyahu only over “the tactics of how to get there.”

Netanyahu says he means no disrespect to Obama but is morally obliged to warn against any deal that might leave open the way to a nuclear-armed Iran.

The speech comes just two weeks ahead of a tight national election in which Netanyahu is fighting to hold onto his job. Obama does not plan to meet with Netanyahu while he’s in Washington, saying he wants to avoid any perception that he is meddling in Israel’s election.

In a warm-up address to America’s leading pro-Israel lobby on Monday, Netanyahu said he would speak to Congress “about an Iranian regime that is threatening to destroy Israel, that’s devouring country after country in the Middle East, that’s exporting terror throughout the world and that is developing, as we speak, the capacity to make nuclear weapons – lots of them.”

The Israeli leader is deeply suspicious of international efforts to reach a nuclear deal, fearing the U.S. and its negotiating partners will give Iran too many concessions.

That puts him on a collision course with Obama, who has put his prestige on the line to pursue a deal.

The U.S. and Iranian sides met for two hours on Tuesday morning in the Swiss resort of Montreux, according to U.S. officials. They likely will continue meeting through Netanyahu’s speech. Both sides said they were making progress.

“We’re working away, productively,” U.S. Secretary of State John Kerry told reporters.

Netanyahu believes that preventing a nuclear-armed Iran would be his crowning achievement – and that a bad deal would be a setback and far worse than no deal at all. While powerful, his speech to Congress also might sound a note of desperation as he appears almost out of options.

As many as 40 members of the House and more than a handful of senators are expected to skip the speech, which many have labeled a partisan political stunt. Vice President Joe Biden, president of the Senate, also won’t be there. He’s on a trip to Central America and his seat on the dais will be filled by Sen. Orrin Hatch, president pro tempore.

Many Democrats will be in the audience, however. Sen. Joe Manchin, D-W.Va., said he would attend “to find out more about the prime minister’s point of view on this.”

Hatch, R-Utah, said Monday that Congress should complement the prime minister’s address with the threat of more sanctions.

“I am deeply troubled that our president’s solution won’t work,” Hatch said. “This administration has opted for a policy of conciliation that does nothing to curb this growing threat. And all the while, the threat to Israel grows stronger every day.”

Netanyahu expressed frustration that his speech has created such controversy. He insisted that his speech to Congress was not meant to show any disrespect toward Obama or the Oval Office. He also said it was not intended to “inject Israel into the American partisan debate.”

But that is what’s happened.

Members of Congress who are expected to be no-shows at the speech blame House Speaker John Boehner for inviting Netanyahu without consulting with the White House or congressional Democrats. Obama’s national security adviser Susan Rice has said the speech is destructive to the fabric of U.S.-Israeli relations.

Kerry has said Netanyahu should hold his criticism until he knows the details about a deal – if one materializes.

Kerry said Monday in Geneva that negotiators are seeking a verifiable set of commitments that its nuclear program is peaceful. He said that “any deal must close every potential pathway that Iran has towards fissile material, whether it’s uranium, plutonium, or a covert path. The fact is only a good, comprehensive deal in the end can actually check off all of those boxes.”

Kerry is meeting this week with Iran’s foreign minister, Mohammad Javad Zarif.