Factbox-Who is fighting in Yemen?

DUBAI, Oct 6 (Reuters) - Saudi-backed Yemeni government forces have staged a counteroffensive to retake the coast around the Bab el-Mandeb shipping route and other strategic territory seized last month by the Iran-aligned Houthis, in a complex conflict with shifting alliances.

Below are the factions involved in the 12-year-old civil war which erupted after the Houthis seized the ​capital Sanaa, prompting a Saudi-led military intervention. A UN-brokered truce in 2022 largely halted heavy fighting, but it did not lead to a lasting settlement, with a spillover from the Iran conflict triggering the latest fighting.

A'AMALIQA (The Giants)

This military formation, which is leading most of the charge against the Houthis, consists mostly of students of the ultra-conservative Sunni Salafi in the south. They appeared on the scene in 2016. This group, like others, split into factions, complicating efforts to stabilise Yemen, the most impoverished Arab state.

The largest one is led by hardliner Abu Zara Al-Muharrami, a member of Yemen's Presidential Leadership Council, who is now managing military operations along the vital Red Sea coastline overlooking Bab el-Mandeb. Another faction has remained loyal to the United Arab Emirates, which pulled its forces out of Yemen in January after a dispute with its former ally in the war, Saudi Arabia. A third faction, called Homeland Shield Forces, defected from its alliance with the UAE and is now supported by Saudi Arabia.

THE HOUTHIS

The Yemeni conflict was triggered when the Houthi movement, formally named Ansar Allah, ousted the Saudi-backed, internationally recognised government of then-President Abd Rabbu Mansour Hadi in late 2014.

The group remains the dominant military force in the country, controlling the capital Sanaa and much of the north. It is estimated to control territory where between 60% and 65% of Yemenis live.

The Saudi-led coalition accuses Iran of arming, training and funding the Houthis. The group denies being an Iranian proxy and says it develops its own weapons. Tehran also rejects the allegations.

The Houthis have demonstrated their missile and drone capabilities during the Yemen war in attacks on Saudi Arabia and the UAE, targeting oil installations and vital infrastructure.

Widely seen as part of a regional alliance known as the "Axis of Resistance" backed by Iran, the Houthis have also rallied behind the Palestinians in the Gaza war, lobbing drones and missiles at Israel and attacking commercial shipping in the Red Sea.

The Houthis entered the current war alongside Iran with an attack on Israel on March 28, but largely stayed quiet before declaring a naval blockade against Saudi Arabia in July and stepping up attacks against the south of the kingdom in September.

The Houthis have proven resilient, defying over 10 years of bombing by the Saudi-led coalition, as well as US and British strikes in recent years.

SAUDI ARABIA

Riyadh entered Yemen when it led a military coalition against the Houthis in March 2015, seeking to restore Hadi's government. Saudi Arabia sought to prevent an Iran-aligned group from consolidating power on its southern border.

Riyadh and Tehran, despite a China-brokered thawing of relations, have long been regional rivals and deeply distrust one another.

The kingdom, the world's largest oil exporter, signed in August a defence pact with Turkey and Pakistan in response to growing regional instability from the US-Israeli war on Iran. The Houthis have been attacking energy infrastructure in Saudi Arabia.

THE SAUDI-BACKED GOVERNMENT

The eight-member Presidential Leadership Council, led by Rashad al-Alimi, is the internationally recognised Yemen authority based in the port city of Aden. It was formed in Riyadh in April 2022 to replace former president Hadi and unify anti-Houthi forces, but the council has been paralysed by the divisions it was meant to solve. The government is heavily reliant on Saudi air power as it tries to reverse Houthi gains.

NATIONAL RESISTANCE FORCES

The National Resistance Forces are a well-equipped anti-Houthi force led by Tarek Saleh, a nephew of former Yemeni president Ali Abdullah Saleh and a member of the Presidential Leadership Council. Originally established with UAE support to battle the Houthis on Yemen's west coast, the force has maintained ties to Saudi Arabia and aims for a unified Yemen, positioning itself as a counterweight to both the Houthis and southern secessionists.

On September 10, Saleh told his forces on the west coast to regroup and establish an alternative command centre in a safe location, as Houthi fighters seized territory.

STC

The Southern Transitional Council, which was trained and equipped by the United Arab Emirates, sought secession for the south — an independent state until unification with the north in 1990 — in January. The southern leadership at the time tried to secede in 1994 but was swiftly beaten by then-President Ali Abdullah Saleh's army.

The STC, led by Aidarous al-Zubaidi, is part of the Saudi-led coalition but declared in 2020 it would establish self-rule in the south. Tensions peaked in December 2025 when the group seized large swathes of land in Hadramout and Al Mahra provinces and swept to the borders of Saudi Arabia, challenging the regional heavyweight's influence.

ISLAH PARTY

The Yemeni Congregation for Reform, better known as al-Islah, is a Sunni Islamist movement with historic ties to the Muslim Brotherhood. It is a key faction within the recognised government but is viewed by the UAE and the STC as a terrorist organisation. Its major stronghold has long been Marib, the country's sole gas-producing region with one of its largest oilfields.

UAE

The UAE joined the Saudi-led coalition and was among its most effective ground forces. A withdrawal of UAE troops was announced in 2019 and completed in 2020, but it maintained influence on the ground through the STC and other factions.

The UAE was motivated by its antipathy towards the Muslim Brotherhood and securing shipping lanes in Bab el-Mandeb and Gulf of Aden, analysts said.

The UAE pulled all its remaining forces out of Yemen in January after a dispute with its former ally in that war, Saudi Arabia.

(Writing by Nayera Abdallah and Michael Georgy; Editing by Hugh Lawson)