The primary source of Iran– Iraq border disputes has been Iraq’ s claims to ownership and navigational rights over the Arvand Rud, in addition to its demands for controlling several strategic border points. Among Iran’ s neighbors, Iraq shares the longest common border at 1,608 kilometers.⁠[1] From the very beginning, Iraq has claimed sovereignty over several border areas.

The history of Iran-Iraq border disputes dates back to the establishment of the Safavid dynasty in Iran and the Ottoman Empire (of which Iraq was a part).⁠[2] During this period and up to the fall of the Ottoman Empire, the main causes of conflict were, on one side, ambitions for territorial expansion, and on the other, efforts to curb the spread of the rival power’ s religious doctrine, given that Iran was the leading Shia state and the Ottomans the foremost Sunni power in the Islamic World.⁠[3] After the Ottoman Empire collapsed and a new state was formed in Iraq, the disputes narrowed mainly to the use of water resources in the Arvand Rud north of the Persian Gulf.

Unlike Iran, which lies along the northern shores of the Persian Gulf and controls a large part of the Sea of Oman, Iraq has no suitable coastline. Iraq has the shortest shoreline on the Persian Gulf— roughly 55 kilometers— much of it shallow and unsuitable for constructing reliable deep‑water ports. Confronted with this geographic bottleneck, successive Iraqi governments adopted an expansionist approach. Since gaining independence in 1932, this strategy has been directed primarily toward its two immediate neighbors, Iran and Kuwait.

By dominating the water resources of Iran and Kuwait, Iraq could reach deeper waters, which enabled the country to play a more active and influential role in the Persian Gulf and paved the way for its expansionist agendas.⁠[4]

In addition to the dispute over ownership and use of the Arvand Rud, certain strategic border points— such as the Meimak City and Konjan-Cham village in Ilam Province— have been major sources of contention. These locations are of special military importance for both sides because they provide commanding views over the border areas. One of the most intense clashes during the Pahlavi era occurred on February 10, 1974, when Iraqi troops attacked Hill 343 near Konjan-Cham village on the Mehran– Ilam Road, which overlooks the Badra plain in Iraq, and occupied it. After several hours of heavy fighting, Iranian forces recaptured the hill at 2:00 AM the next day.⁠[5]

Until 1976, efforts by the two countries to resolve border disputes led to a series of agreements such as the Kordan (1746),⁠[6] Erzurum (1823 and 1847),⁠[7] Constantinople (1724),⁠[8] and Tehran (1911),⁠[9] yet none ultimately satisfied Iraq. Military confrontations between Iranian and Iraqi forces took place in 1969,⁠[10] 1972,⁠[11] and 1973.⁠[12] Finally, during the OPEC summit in Algiers in 1975, Saddam Hussein and the Shah of Iran reached an agreement: Iran would stop supporting Masoud Barzani— who opposed Saddam and was fighting for the separation of Iraqi Kurdistan— and cede part of the Meimak area in Ilam Province to Iraq. In return, Iraq recognized Iran’ s sovereignty over the eastern half of the Arvand Rud.⁠[13] and⁠[14]

During the second Pahlavi era, Iraq also raised non-shared borders with Iran as part of its strategy to press its claims. For example, in the late 1960s, Iraq tried to link the Baluch people living in eastern Iran to Arab origins, in an attempt to create a distinct Sunni Arab identity for them in opposition to the majority Shia Persian population. As a result, the most important Iranian Baluch political organization opposed to the Pahlavi regime— the Baluchistan Liberation Front— became active under direct political, financial, and military support from Iraq’ s Baath Party, with its main headquarters in Baghdad. In exchange for financial aid from the Baathist regime, the Front agreed to endorse Iraq’ s and certain other Arab states’ claims over Khuzestan and to accept Iraq’ s claim of full sovereignty over the Arvand Rud.⁠[15] Meanwhile, Iraq supported the Persian Gulf sheikhdoms’ claims to Iran’ s three islands (Abu Musa, Greater and Lesser Tunb) and the Persian Gulf itself. It portrayed Iran— despite its more than 1,000‑kilometer coastline— as a foreign power in the Persian Gulf region, used fabricated names for the Persian Gulf, claimed that the Persian Gulf belonged to the Arabs and that Iran had occupied it, and even compared Iran to the Zionist regime, calling the Persian Gulf the “ second Palestine”.⁠[16]

Beyond disputes over border rivers, the idea of separating Khuzestan and annexing it to Iraq has long been a broader goal of Iraqi rulers. During the eight-year Imposed War, Iraqi media repeatedly promoted this ambition. Iraq’ s invasion of Iran had two probable territorial objectives: a maximum goal of annexing Khuzestan, and a minimum goal of abrogating the 1975 Algiers Agreement. That is why, at the start of the war, Iraq crossed the Arvand Rud into Khuzestan— where most residents are Arabic-speaking— and explicitly stated its aim was to “ liberate Arabistan” (Iran’ s Khuzestan).⁠[17]

A new round of border disputes began after the victory of the Islamic Revolution. At that time, Iraq withdrew from the ongoing joint border demarcation project (piling and marking) that had started under the Pahlavi regime.⁠[18] Two years after the Revolution, when the Iranian Army was still struggling with post-revolutionary challenges, the Iraqi government delivered an official note to the Iranian embassy in Baghdad on September 17, 1980, unilaterally abrogating the 1975 Agreement. One week later, on 22 September 1980, Iraq launched a full‑scale invasion of the Islamic Republic of Iran with twelve combat divisions, striking airports and economic facilities in several Iranian cities and attacking from land, air, and sea against military bases, installations, and commercial vessels.⁠[19] This imposed an eight-year war on Iran. However, after the war ended, Saddam Hussein wrote to President Akbar Hashemi Rafsanjani affirming Iraq’ s commitment to the 1975 Agreement and backing away from the positions that had led to the eight-year conflict.⁠[20]

Even after the Iran-Iraq War ended and relations between the two countries normalized, border disputes have persisted. In 1988, Iraq announced plans to dig a new waterway to divert the Arvand Rud about 20 kilometers away from the Iranian border, turning it into an entirely internal Iraqi river. The project, however, failed due to high financial costs and geographical challenges.⁠[21] After the fall of the Baath regime, Jalal Talabani, Iraq’ s first president after Saddam, stated that Iraq considered the 1975 Algiers Agreement null and void.⁠[22] But, following reactions in both Iran⁠[23] and Iraq,⁠[24] he retreated from that position and reaffirmed the treaty’ s validity.⁠[25] In another instance, in 2009, the Iraqi government claimed that Iran had taken actions on border rivers that reduced the water flow into Iraq. Iran’ s Deputy Foreign Minister rejected the claim and expressed readiness for technical negotiations on dividing the border river waters and determining each country’ s share. He noted that the 1975 Algiers Agreement did not specify exact water shares for each side, and a joint commission of experts from both countries was working to determine them. He also recalled the 2008 agreement between Iran and Iraq to resolve all outstanding issues based on the 1975 treaty.⁠[26]