Iran’s influence in the Middle East

Concern about Iranian foreign policy is not limited to its nuclear programme, but also to its proxy forces and alliances with violent groups across the Middle East, several of which are UK-designated terrorist organisations.

Since the Iranian revolution of 1979, when the Shah was overthrown and Ayatollah Khomeini returned to the country, the Iranian regime has sought to embed its influence across the region.

To do this, Iran has countered conventional military forces with a network of associated militia groups and other non-state actors, starting with Hezbollah in Lebanon in the 1980s. The Islamic revolutionary guard corps (IRGC) Quds force has been key to this process.

Instability and weak states in Lebanon (from the 1980s), Iraq (from 2003) and Yemen (from 2014) provided a space for Iran to develop alliances with Lebanese Hezbollah, Iraqi militias, and Yemen’s Houthis. In the Occupied Palestinian Territories, Hamas and Palestinian Islamic Jihad also receive Iranian support. Iran is a long-standing ally of Syria and its President Assad.

This briefing describes Iran’s activity in five arenas in the Middle East, what the UK and its partners have done in response, and the situation in 2024.

Why does Iran seek greater influence?

International Crisis Group cites several reasons for Iran’s strategy:

• To seek to secure the regime through a “forward defence” strategy, meaning it battles its enemies in other states (such as Lebanon, Iraq).
• Iran is a Shia-Muslim majority state, while most regimes in the Middle East are governed by Sunni Muslim rulers—notably Saudi Arabia, one of its significant regional rivals. Iran claims to act to protect Shia Muslims.
• To combat the United States and Israel and regional competitors.

Where is Iran influential, and why?

Iran has targeted weak states and generally supported non-state actors that are carving out areas of autonomy within them. The primary exception is its long-standing alliance with Syria’s ruling President Bashar al-Assad, which has strengthened during the country’s civil war. In summary:

• Iran has supported Lebanese Hezbollah since Lebanon’s civil war in the 1980s. Hezbollah maintains a separate military force to the state and provides basic services in areas with substantial Shia Muslim populations (from where it gets a majority of its support). The absence of a president in Lebanon since 2022 constrains the ability of its government to act.
• Following the US-led invasion of Iraq in 2003 and the arrival of Islamic State/Daesh in the mid-2010s, Iran has financed and trained Shia militia groups which stand as a separate force to Iraq’s military. Political groups associated with them performed well in the latest local elections in 2023. There are negotiations on withdrawing US troops from Iraq.
• In Yemen’s civil war, Iran has supported the Houthis, who oppose the internationally recognised government (which a Saudi-led military coalition has intervened to support). Expectations for a political settlement dissipated because of Houthi attacks on shipping in 2023/24.
• In Syria, President Assad was opposed by Gulf Arab states when conflict broke out in the country in 2011/12. Iran has provided significant military and economic support to his regime, as has Russia. Gulf states are now beginning to reconcile with Assad. This may dilute Iran’s influence.
• In the Occupied Palestinian Territories, from the 1980s Iran has supported groups including Hamas and Palestinian Islamic Jihad. The US does not believe Iran planned the 7 October 2023 assault on Israel.

Outlook for Iran’s foreign policy

Talks to re-establish the 2015 nuclear agreement stalled in 2022, when they were reportedly in their final stage. The backdrop of Iran’s support for Russia in Ukraine, criticism of its response to the 2022 Mahsa Amini protests, and regional escalation since October 2023, offer challenges to new talks.

Some elements of the 2015 agreement, such as the UN arms embargo on Iran and UN prohibition on exporting and importing certain missiles and drones, have now expired (though the UK, EU and US have continued these sanctions).

The US and UK remain committed to Iran never acquiring a nuclear weapon. Iran’s competitors in the region, such as Saudi Arabia, have previously called for any new nuclear agreement to be widened to curtail Iran’s wider military activity. Whether any potential agreement would curtail Iran’s wider influence in the region is unknown, but unlikely. In 2022, the Iranian Government rejected the notion that matters of “national strength” were for negotiation.

Iran joining the BRICS bloc of economies in 2024 (including China, and alongside the UAE and Egypt) is seen as an attempt to combat its global isolation as part of its “look east” policy. However, US sanctions impede the degree to which Iran can trade. Iran’s new president is seeking the removal of sanctions and says he is committed to reviving the 2015 nuclear agreement. However, it is Iran’s supreme leader who dominates Iranian foreign policy.