Israeli Prime Minister Benjamin Netanyahu warned in an address to the U.S. Congress that Iran is a threat to the region and the world, and that a potential nuclear deal with the regime would not stop it from getting a nuclear weapon.
"The deal will not prevent Iran from having nuclear weapons. It would all but guarantee Iran gets nuclear weapons," he said.
Netanyahu said that the deal would give Iran a short "breakout" time to get a nuclear weapon.
The Israeli prime minister said that Iran was a regional threat in the Middle East, that it "dominates" in Iraq, Lebanon, Yemen, and Syria.
He also said that Iran's regime was a "grave threat" to the state of Israel.
Netanyahu drew attention to the conflict in Iraq, where a U.S.-led coalition and Iranian forces are separately helping the Iraqi government battle militants from the so-called Islamic State militant group.
He said that Iran was no friend to the United States in the fight against IS militants. "So when it comes to Iran and ISIS, the enemy of your enemy is your enemy," he said, using another name for the group.
He said that both Iran and the so-called Islamic State "want to impose a militant Islamic empire, first on the region, and then onto the entire world."
Accrdomg to the IRNA news agency, then Iranian Foreign Ministry spokeswoman dismissed the speech as "boring and repetitive" and "part of the hard-liners' election campaign in Tel Aviv."
The Israeli prime minister said he was grateful to U.S. President Barack Obama for his support of Israel. However, the speech was sharply critical of a possible deal on Iran's nuclear program.
Obama said Netanyahu didn't offer any "viable alternatives" to the nuclear negotiations with Iran.
Obama said he read a transcript of Netanyahu's speech on March 3 and that it contained "nothing new."
The United States, Britain, China, France, Germany, and Russia have been negotiating with Iran for years in an effort to curb its nuclear program, which Western governments fear is aimed to develop nuclear weapons capability. Tehran denies this.
After missing two self-imposed deadlines last year, the six powers and Iran agreed to seek a political framework agreement by March and a comprehensive deal by June 30.
Administration officials frequently point out that no deal has been reached, therefore making it impossible to criticize a deal.
House Speaker John Boehner (Republican-Ohio) invited Netanyahu to speak, breaking with typical protocol that the White House makes invites for foreign leaders.
National Security Adviser Susan Rice called Netanyahu's visit "destructive" to U.S.-Israel relations on February 24. Secretary of State John Kerry, however, downplayed tensions on March 1, saying the Israeli prime minister was welcome in the United States at any time.
Kerry, who Netanyahu called a "longtime friend," is in Switzerland negotiating with Iran on its nuclear program.
The Israeli prime minister said that the United States should continue to maintain sanctions on Iran, and look for a "much better deal" with Iran.
"This is a bad deal, it's a very bad deal, we're better off without it," said Netanyahu.
Netanyahu's remarks were generally met with big applause from members of Congress.
But the speech was boycotted by as many as 40 House Democrats and several Senate Democrats, many of whom complained that the speech is injecting an element of partisanship into the U.S.-Israel relationship.
Netanyahu denied the charge. "I deeply regret that some perceive my presence here as political, that was never my intention," he said.
U.S. House Minority Leader Nancy Pelosi (Democrat-California) said the speech was an "insult to the intelligence of the United States" and she was "near tears" throughout the oration.
The speech comes two weeks before electio ns in Israel. Obama will not meet with him, to avoid the appearance of interfering in Israel's election.
U.S. Vice President Joe Biden, who normally presides over such speeches, did not attend the speech because he is in Guatemala. The White House said Obama would not be watching it either.