Why are Iran and Israel sworn enemies?

Iran and Israel have been enemies for the past few decades with Iran saying it wants to wipe Israel off the map and threatening to annihilate it. Israel, for its part, regards Iran as its biggest adversary.

But this wasn't always the case.

When were Iran and Israel allies?

In fact, Israel and Iran were allies until Iran's 1979 Islamic Revolution. Iran was one of the first states to recognize Israel after it was founded in 1948. Israel regarded Iran as an ally against the Arab states. Iran, meanwhile, welcomed US-backed Israel as a counterweight to the region's Arab countries.

Back then, Israel trained Iranian agricultural experts, supplied technical know-how and helped build up and train the Iranian armed forces. The Iranian shah paid Israel in oil, as its burgeoning economy was in need of fuel. 

Not only that. Iran was home to the second-largest Jewish community outside of Israel. Yet, after the Islamic Revolution, many Jews left the country. That said, even today, more than 20,000 Jews still live in Iran.

When did Israeli-Iranian relations change?

After the Iranian Islamic Revolution brought Ayatollah Ruhollah Khomeini and his religious revolutionaries to power, Iran scrapped all previous agreements with Israel. Khomeini directed fierce criticism at Israel for its occupation of Palestinian territories.

Gradually, Iran adopted an increasingly harsh rhetoric toward Israel with the aim of winning the favor of regional Arab states, or their citizens at the very least. The Iranian regime, after all, was eager to grow its regional influence.

When Israel sent troops into southern Lebanon in 1982 to intervene in the country's civil war, Khomeini dispatched Iranian Revolutionary Guards to the Lebanese capital, Beirut, to support local Shiite militias. The Hezbollah militia, which grew out of this support, is today regarded as a direct Iranian proxy in Lebanon.

Iran's current leader, Ayatollah Ali Khamenei, who has the final say in all matters, remains just as antagonistic toward Israel as his predecessors. Khamenei and the entire Iranian leadership have also repeatedly questioned and denied the Holocaust.

Should Iran change its anti-Israel stance?

Not all ordinary Iranians support Iran's hostility toward Israel.

"Iran must reassess its relationship with Israel because its stance is no longer in keeping with the times," said Faezeh Hashemi Rafsanjani, the daughter of former Iranian President Ali Akbar Hashemi Rafsanjani, in a 2021 interview. Faezeh Hashemi Rafsanjani, who once held a seat in Iran's parliament, said Muslim Uyghurs are oppressed in China and Chechen Muslims in Russia — and yet "Iran has close relations with both."

Prominent political scientist Sadegh Zibakalam has repeatedly criticized Iran's policy toward Israel. "This stance has isolated the country on the international stage," Zibakalam said in a 2022 interview with DW.

Staunch backers of Iran's Islamic Republic, however, support the country's hostile position against Israel and are keen to see it oppose the great powers.

Some Iranian regime supporters and members of the so-called Axis of Resistance have been irritated by Iran's long reluctance to attack Israel in the context of the Gaza war or avenge attacks on Iran itself, analyst Ali Fathollah-Nejad said in April 2024. The director of the Berlin-based Center for Middle East and Global Order think tank explained that frustration was growing over "Iran's lack of credibility as the main champion of the Palestinian cause and its hesitance to confront Israel directly."

This article was originally written in German and published in April 2024. It was updated on 13 June 2025, following the Israeli attack on Iran.

Shabnam von Hein German-Iranian journalist at DW's Asia department