My report, ‘Regime Collapse in Iran: A Necessity for Regional Stability?’ identifies the risk of the Iranian regime collapsing, with no transition plan is in place. In such a scenario, regional actors could take advantage of the vacuum of governance and coopt armed secessionist groups. This can advance the neighbouring states’ bid to extend their spheres of influence, and take territory.[1]
These regional actors could include:
- Saudi Arabia that could back Arab separatists in Khuzestan to destabilise regime influence.
- Turkey that may intervene to prevent Kurdish unification or secession in Iranian Kurdistan, similar to its posture in Iraq and Syria.
- Syria and Iraq would resist Kurdish independence efforts.
- Pakistan could also become involved to secure its border with Baluchestan due to its long struggle with cross border Baluch insurgents.
- Azerbaijan’s could intervene in Iran’s north western region on behalf of the Azeris. This could have a broader ripple effect throughout Iran as Azeris have migrated to central Iran to areas including Tehran, Karaj and Qum.
There is recent historical precedence for collapsing or weakened states being preyed upon by ambitious neighbours, so this fear is not without basis in reality. Some examples include:
- Russia’s annexation of Crimea in 2014
After Ukraine’s 20114 Euromaidan revolution, Ukrainian pro-Russian President Viktor Yanukovych fled the country, and Ukraine’s government was overthrown. Russia used the power vacuum that followed as a pretext for its military intervention and subsequent illegal annexation of Crimea. This move sparked the ongoing Russia-Ukraine conflict. [2]
- India’s annexation of Hyderabad and Sikkim 1948-1975
The state of Hyderabad resisted joining India post British exit. In 1948, India launched Operation Polo, a military intervention to annex Hyderabad claiming that its independent could lead to chaos.[3]
Sikkim was initially a protectorate and experienced unrest and a power vacuum. In 1975 India oversaw a referendum and annexed Sikkim as an Indian state.[4]
- Moroccan takeover of Western Sahara 1976-1979
After Spain withdrew from Western Sahara in 1975, a vacuum emerged causing in 1976-1979 for Morocco to claim the territory through partition agreements. Morocco’s conflict with the local Polisario Front centering around the disputed territory of Western Sahara still endures.[5]
- Fall of Saddam Hussein in Iraq 2003
The 2003 US led invasion toppled Saddam Hussein’s government, leading to a power vacuum, which, along with the Coalition Provisional Authority’s mismanagement (e.g., disbanding the Iraqi army), contributed to a sectarian civil war and a lengthy insurgency. This situation, along with the existing strong Shia-Sunni divide and historical tensions, allowed Iran to extend its influence in Iraq.[6]
Iran cultivated ties with Shia political parties and militias, providing them with support, funding and training. The rise of ISIS in 2014 further solidified Iran’s role, as Iran backed Shia militias became a crucial part of Iraq’s fight against the extremist group.
- Fall of the Assad regime and Turkey projection of influence
Prior to the collapse of the Assad regime, Turkey sought reconciliation with Assad to by establish a buffer zone to weaken Kurdish militias and to discuss the resettlement of Syrian refugees. These efforts were unsuccessful, and Turkey shifted its support to the Syrian National Army and other opposition groups which contributed to the offensive that led to the regime’s collapse.
Turkey seeks to prevent the resurgence of terrorist groups like ISIS and ensure that areas near its border are free from extremism. Turkey has hosted almost 3 million Syrian refugees, and wants to prevent further refugee flows. Economically, Turkey wants to position itself as a leading role in the reconstruction of Syria, offering opportunities for Turkish companies.
- Fall of the Assad regime and Israel’s projection of influence
Israel fears hostile Sunni Islamist and Turkish forces from establishing a foothold that could threaten its security. To this end, in the aftermath of the fall of the Assad regime, Israel increased airstrikes and ground operations, especially in the southern Syrian region and the Golan Heights. At a strategic level, Israel has pushed back Iran’s sphere of influence, and to prevent the new government from acquiring the previous regime’s chemical weapons, sophisticated air defence systems, anti-aircraft guns and other military equipment. In early June 2025, when projectiles landed in the Golan, Israel responded with airstrikes and artillery fire in Daraa and Quneitra provinces, holding the interim Syrian government under al-Sharaa responsible. [7]
In the event of a collapse of the Iranian regime, the West must be ready. Drawing on the experiences of these historical examples will be vital, as will a credible strategy for a transitional period.
Western States have failed to formulate a strategy for promoting defections from within the IRGC and Iranian military. This would be essential during a transition period, as it could enable security units to maintain internal order in bordering regions during what would be a very fluid time. This would prevent a repeat of the widescale disorder and violence that followed the American invasion of Iraq in 2003, aggravated by the de-Baathification of the security forces. Western states must already now begin coordinating with neighbouring states to stabilise bordering regions in the event of regime collapse which could prevent further fragmentation. Despite surrounding states capitalizing on ensuing chaos to extend their respective spheres of influence into Iran, they have a vested interest in not having a complete vacuum of governance with chaos spilling over from its borders. My report makes the policy prescription that Western states must diplomatically engage with Iran’s surrounding states for them to develop capacity building, training and support among opposition groups. At the same time, they can develop strategies for building coalitions, and contributing to developing transition plans.
[1] International Crisis Group, ‘A Time for Talks: Toward Dialogue between the Gulf Arab States and Iran’, 2021, Accessed from: https://www.crisisgroup.org/middle-east-north-africa/gulf-and-arabian-peninsula/iran-united-arab-emirates-saudi-arabia-qatar#:~:text=The%20rise%20of%20Mohammed%20bin,more%20confrontational%20course%20toward%20Iran.&text=Bin%20Salman%20made%20containing%20and,the%20Arab%20world%20and%20elsewhere”.&text=Crisis%20Group%20interview%2C%20Riyadh%2C%20March,state%20allies%20without%20U.S.%20pressure.&text=Crisis%20Group%20interviews%2C%20Riyadh%2C%20March,attack%20by%20its%20larger%20neighbour. See Appendix for historical examples of regional powers exploiting power vacuums of neighboring states.
[2] Allan, Duncan et al., ‘Myths and misconceptions in the debate on Russia’, 2001, Chatham House, Accessed from: https://www.chathamhouse.org/2021/05/myths-and-misconceptions-debate-russia Zasenko, Okeska et al., ‘The crisis in Crimea and eastern Ukraine’, 2025, Britannica, Accessed from: https://www.britannica.com/place/Ukraine/The-crisis-in-Crimea-and-eastern-Ukraine
[3] Sharma, Mimansa, ‘September 17 1948: Operation Polo; the violent history of Hyderabad’s annexation’, 2024, The Saisat Daily, Accessed from: https://www.siasat.com/sept-17-1948-operation-polo-the-violent-history-of-hyderabads-annexation-2414636/
[4] Eurasian Times, ‘16th May 1975: The Kingdom of Sikkim and its Annexation with India’, 2018, Eurasian Times, Accessed from: https://www.eurasiantimes.com/sikkim-history-india-annexed/
[5] Chograni, Houda, ‘The Polisario Front, Morocco, and the Western Sahara Conflict’, 2021, Arab Centre Washington DC, Accessed from: https://arabcenterdc.org/resource/the-polisario-front-morocco-and-the-western-sahara-conflict/
[6] Ahouie, Mahdi and Tefagh, Mohammed, ‘A Difficult Friendship: Elements of Continuity and Change in Iran-Iraq Relations in Post-Saddam Era’, 2024, Journal of World Sociopolitical Studies, Accessed from: https://wsps.ut.ac.ir/article_99316.html#:~:text=The%20power%20vacuum%20that%20followed%20the%20removal,Shia%20political%20groups%20and%20militias%20within%20Iraq.
[7] Lapin, Yaakov and Zehavi, Sarit, ‘Power Struggles in Syria after the Assad Regime: Mapping the Competing Interests’, 2025, Alma Research and Education Centre, Accessed from: https://israel-alma.org/power-struggles-in-syria-after-the-assad-regime-mapping-the-competing-interests/
