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Twelve-Day War

The Twelve-Day War was a brief armed conflict between Israel and Iran in June 2025, marked by Israeli strikes on Iranian nuclear and military targets and Iranian retaliatory attacks.

By Ethan Anderson| Reviewed by Olivia Bennett, Standards & Fact-Checking Lead| Updated July 26, 2026|2 min read| Fact-checked

The Twelve-Day War was a brief armed conflict between Israel and Iran that took place from 13 June to 24 June 2025. The war began with Israeli strikes on Iranian nuclear and military targets, followed by Iranian retaliatory attacks, and ended after a U.S.-brokered ceasefire. It is also referred to as the 12-Day War or the Iran–Israel war.

Background

The Twelve-Day War emerged from the wider Iran–Israel conflict, which had involved years of proxy hostilities and direct confrontations before June 2025. The conflict formed part of the longer-running Iran–Israel conflict, which had already included direct clashes in 2024.

Course of the war

Israel opened the conflict on 13 June 2025 with large-scale strikes on Iranian nuclear, military, and related infrastructure, under the name Operation Rising Lion. Iran responded with missile and drone attacks, dubbed Operation True Promise III, targeting Israel. The United States later entered the conflict on 22 June 2025, striking Iranian nuclear facilities under Operation Midnight Hammer.

Ceasefire

A ceasefire was announced on 23 June 2025 and was described as taking effect the following day, 24 June 2025. Reports indicate that the fighting ended shortly after the ceasefire came into force, despite some early violations. The ceasefire was brokered by the United States.

Aftermath

The war affected regional security and intensified debate over Iran's nuclear programme, Israeli military strategy, and U.S. involvement in the Middle East. Public reporting on casualties and damage varied by source, with estimates differing across outlets.

Key facts

  • The war began on 13 June 2025 with Israeli strikes on Iranian nuclear and military infrastructure.
  • Iran responded with missile and drone attacks on Israel during the same period.
  • The United States later entered the conflict by striking Iranian nuclear facilities on 22 June 2025.
  • A ceasefire was announced on 24 June 2025, bringing the fighting to an end.
  • The conflict formed part of the longer-running Iran–Israel conflict, which had included direct clashes in 2024.
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Canadian context

The war mattered to Canadian readers because it affected global energy markets, Middle East security, and international diplomacy, all of which can influence Canadian foreign policy and economic conditions.

Frequently asked questions

What was the Twelve-Day War?
It was a brief armed conflict in June 2025 between Israel and Iran, ending after a U.S.-brokered ceasefire.
When did the Twelve-Day War start?
It began on 13 June 2025, when Israel launched strikes on Iran.
When did it end?
The conflict ended with a ceasefire announced on 24 June 2025.
Did the United States take part?
Yes. The United States later struck Iranian nuclear facilities and helped broker the ceasefire.
What were the main operations called?
Israel’s operation was called Operation Rising Lion, Iran’s response was Operation True Promise III, and the U.S. strikes were called Operation Midnight Hammer.

References

  1. Encyclopaedia Britannicahttps://www.britannica.com/event/12-Day-War
    Supports: Date, parties involved, U.S. involvement, and ceasefire timing.
  2. Wikipediahttps://en.wikipedia.org/wiki/Twelve-Day_War
    Supports: Common name, conflict timing, and Trump's use of the term '12 Day War'.
  3. Simple English Wikipediahttps://simple.wikipedia.org/wiki/Twelve-Day_War
    Supports: Start date, naming, and broad description of the conflict.
  4. Al Jazeerahttps://www.aljazeera.com/news/2025/6/26/visualising-12-days-of-the-israel-iran-conflict
    Supports: Timeline of Israeli, Iranian, and U.S. strikes; ceasefire date; casualty reporting.
  5. Wikipediahttps://en.wikipedia.org/wiki/Iran%E2%80%93Israel_conflict
    Supports: Context within the longer Iran–Israel conflict and prior direct clashes.
  6. Wikipediahttps://en.wikipedia.org/wiki/List_of_attacks_during_the_Twelve-Day_War
    Supports: Named operations and sequence of attacks by Israel, Iran, and the United States.