Within the past month, the Iranian-backed Houthis and the Saudi-backed Yemeni forces have reignited a decades-long conflict.
At the heart of renewed fighting is control over the Bab el-Mandeb Strait, a key trading corridor better known as the Gate of Tears.
The Houthis stormed down Yemen's coast in September, seizing the port city of Mocha in a bid for power over the strait.
Now, Yemeni forces have recaptured the city in a major counteroffensive and deployed more than 100 fighter jets to guard the waterway.
But it is a fight that seems anywhere but over.
And one that could impact Australia's supply of everything, from T-shirts to medicine.
What is the Gate of Tears?
The Gate of Tears, or Bab el-Mandeb Strait, is a waterway at the southern end of the Red Sea — between Yemen, Djibouti and Eritrea.
Named for its precarious route, it lies on the opposite side of the peninsula to the Strait of Hormuz, the shipping corridor whose traffic has been dramatically affected as the US and Iran wrestle for its control.
The strait is 29 kilometres wide at its narrowest point, limiting traffic to two channels for inbound and outbound shipments.
The Yemeni island of Perim divides the path.
To the north lie the port cities of Hodeidah and Mocha.The cities, which the Houthis have seized, give a commanding view over approaching vessels.
On September 11, the group also seized the strategic Perim, where the United Arab Emirates — a former Saudi ally — had been building an air base.
Since then, a Saudi-backed counteroffensive has regained control of Mocha and attacked Houthi members in Hodeidah.
What is behind this latest conflict?
The Houthis' desire to control the strait extends beyond the Iran war.
The fight over key ports are part of a continuing civil war in Yemen, between the Houthis and a Saudi-backed government.
From 2015 to the 2022 truce, Saudi Arabia was involved in a combined air and limited ground campaign in Yemen, fighting against the Houthis, a group Australia lists as a terrorist organisation.
The fragile truce collapsed this year, after an air strike hit the Sana'a International Airport, preventing an Iranian flight carrying a Houthi delegation to land.
Houthis blamed the attack on a Saudi-led coalition, and responded with missile and drone strikes on Saudi Arabia, including one that targeted Riyadh.
They also targeted Saudi's oil infrastructure.
In July, the Houthis launched a maritime blockade on Saudi shipping tankers and territory in the Bab el-Mandeb Strait.
The group had conducted a similar attack on commercial ships passing through the strait in 2023—2024, in response to Israel's invasion of the Gaza Strip.
However, this latest blockade exempted non-Saudi vessels.
Mohammed al-Bukhaiti, a member of the Houthis' political bureau, told the Associated Press it wanted Saudi Arabia to lift a long-running blockade on the territory the group controls.
A Saudi counteroffensive has since seen the strait recaptured and tit-for-tat fighting escalate.
Both Saudi and Houthi officials have reported missile strikes and targeted attacks on major airports across Yemen and Saudi Arabia.
The renewed conflict has also seen more than 200,000 Yemenis flee their homes, according to UN estimates.
The United Nations estimated at least 150,000 people — including fighters and civilians — had been killed in Yemen's civil war, which began in 2015.
It had pushed about 5 million people to the "brink of famine".
How important is Bab el-Mandeb to trade?
It serves as the southern gateway to the Suez Canal, meaning ships must pass through it to access the canal from the south.
Before the Iran war in February, about 10-12 per cent of global trade passed through the waterway, Sanjoy Paul, an Associate Professor of Operations and Supply Chain Management at the University of Technology Sydney said.
"It has always been a critical route for shipping," he added.
In 2023, the strait handled approximately 9 per cent of global oil demand, according to the International Sustainable Development Observatory (ISDO).
And for Asia and Australia, the shipping lane is even more significant.
Oil, medicine, fertiliser, textiles, and machinery were all transported through that route, Dr Paul said.
When it was a choke point, ships had to travel around South Africa's Cape of Good Hope which could take three times as long.
"This additional time increases shipping time, increases cost of transportation, increases insurance as well," Dr Paul said.
For customers, that meant shortages and price surges.
Following the Iran war and a battle over the Strait of Hormuz, the Bab el-Mandeb Strait became a "lifeline", Dr Paul said.
Saudi Arabia had built an East-West Pipeline to divert crude oil flows through the Red Sea path
As of June, 3.42 million barrels of Saudi oil flowed through the strait, according to Kpler data.
"This became the alternative route," Dr Paul said.
What does this mean for Australia?
US President Donald Trump has been hesitant so far to become involved in this latest conflict, saying the Houthis "don't want to fight with us".
"They would much prefer not having us involved, and they're letting most ships go through," he told reporters in late September.
But Qatar has warned the world cannot "afford" for the Bab el-Mandeb Strait to close.
"The whole world is going to suffer and it's going to be catastrophic for the entire world," Ibrahim bin Sultan Al Hashmi, Qatar's foreign ministry spokesman, said.
Saudi Arabia exports about 70 per-cent of the global oil supply, and most of its buyers are Asian nations who sell onto Australia.
If the fight for control was to escalate, it might lead to a particularly "devastating impact" on Australia's oil supply, Dr Paul said.
He said a further blockade would be "another blow to shipping and transportation", in addition to decreased use of the Strait of Hormuz.
"That increased demand at a global level will again translate into higher prices," Dr Paul added, about the impact on Australian fuel.
While a chokehold may hit consumer pockets, Dr Paul was concerned about Australia's access to critical supplies, such as medicine.
"It could be another important consideration: How in Australia we can prepare to stock key medicine?" Dr Paul said.
"Because those sort of things will be impacted for a long time.
"We may need to rethink our medical situation, how we can have enough stock here.
