IranIraq

Iran–Iraq relations refer to the diplomatic, political, economic, and security interactions between the Islamic Republic of Iran and the Republic of Iraq. The two neighbouring states share a long border and a common history, religion, and cultural ties, but their relationship has been shaped by competing regional interests and conflicts.

Historically, the border dispute and access to the Shatt al-Arab waterway culminated in the 1975 Algiers Agreement, which established boundaries and navigation rights; Iraq later repudiated the deal in 1980, triggering the Iran–Iraq War (1980–1988). The war was one of the bloodiest in the region, ending with UN Resolution 598 and a stalemate.

After the 2003 invasion of Iraq and the collapse of Saddam Hussein's regime, Iran increased its influence in Iraq through diplomatic channels, economic ties, and support for various political groups and militias. The two countries cooperated in the fight against the Islamic State in Iraq and Syria (ISIS) from 2014 to 2017, with Iran-backed forces playing roles alongside Iraqi security forces.

Contemporary Iran–Iraq relations emphasize border security, trade, and energy ties, including cross-border commerce, water resource management on shared rivers, and collaboration on oil and gas projects. Disputes persist over security, influence, and minority rights, while both countries participate in regional forums and maintain a complex but important bilateral relationship. Relations are also influenced by broader regional dynamics and the involvement of external powers.