In Taez, a city that has been besieged for years by Yemen's Huthi rebels, father-of-five Amin Ghaleb leaves a grocery store empty-handed after haggling fruitlessly with the shopkeeper.

"I can't afford to buy anything," the 50-year-old tells AFP, frowning as he folds his money into his pocket.

It's a familiar tale in the Arabian Peninsula's poorest country, already brought to its knees by nine years of war between the Iran-backed Huthis and a Saudi-led coalition.

Over the past four months, the Huthis have been harassing shipping in the Red Sea in protest at Israel's war against Hamas, triggering American and British reprisal strikes.

The conflict in the commercially vital seaway has pushed up the cost of importing goods, exacerbating runaway inflation and raising fears that, after years of economic crisis, food supplies could run out.

"Prices have doubled and goods are priced either in Saudi riyal or the dollar," said Ghaleb, a government employee who earns about $35 a month.

"How am I supposed to pay rent, electricity, gas, water, food, breakfast, dinner, lunch or clothing for the children?" he asked.

- Slow sales -

Ramadan, when Muslims break their day-long fasts with large evening meals, usually means brisk business for Yemen's shops.

But in a Taez market, customers were few and far between. Shopkeepers were standing idly by, displaying vegetables, herbs and grains in straw baskets outside their stores.

"We are being affected by the poor sales," said Yousif Abduljaleel, a Taez merchant. "Some of our products are spoiling."

Taez's residents have suffered shortages of water, food and humanitarian aid since the Huthis blocked all major roads connecting the city with the rest of the country in 2015.

Concern is now spreading among its inhabitants about the impact of the Red Sea attacks on bringing goods into Yemen, which imports 90 percent of its food and has one of the world's most malnourished populations.

"Yemeni ports could stop receiving goods because of the high risk" of Huthi attacks, said Abdulwase al-Fatki, a Taez resident.

"This has created fears that food stocks will run out," Fatki added.

Mohammed Al-Basha, a Yemen expert for the US-based Navanti research group, said staple goods have become more expensive during Ramadan in areas controlled by Yemen's internationally recognised government.

The price hikes are "affected by the ongoing Red Sea crisis" but also linked to higher demand during Ramadan, reduced humanitarian assistance and a worsening economy, Basha said.

- 'No purchasing power' -

In the rebel-held port city of Hodeida, northwest of Taez, which has been hit by several US and UK reprisal strikes, residents are also worried.

"There is no purchasing power," said Abdulrahman Salam, a Hodeida merchant.

"If the crisis escalates the prices are going to rise even more," he warned.

Meanwhile for Hodeidah's fishermen, their job has become a deadly trade.

Moussa Kulaim, a 50-year-old father of two has been catching fish since he was 12, earning between $4 and $40 for a day's catch.

But these days he is mostly coming up dry due to difficulty navigating Yemen's highly militarised waters.

"It is the only source of livelihood for me and my children," Kulaim told AFP.

"Despite the problems we are facing at sea, we enter for the sake of our livelihood and the livelihood of our children," he said.

"We don't want war, we don't want trouble."