STORY: At Bindal Silk Mills in western India, brightly printed polyester fabric rolls off machines.
The finished fibers are stacked high in carts and sorted by hand.
Inside the mills, workers stir large vats of chemical dye and feed fabric through folding and winding machines.
The factory in Surat produces printed and dyed polyester fabrics for some of the world's biggest retailers, including H&M, Target and Walmart.
But behind this busy scene, there is a serious problem.
The war in Iran has caused fossil fuel prices to increase.
This has squeezed polyester suppliers in India and Bangladesh, and it threatens to increase costs for big retailers.
Chief Executive Avichal Arya says his factory is feeling the pain:
"Two impacts: low productivity because of labor shortage, and high cost of production. So, due to these both scenarios, we are not able to actually meet the demands of the global orders."
Polyester, made from oil-based chemicals, makes up 59% of global fiber production.
One major Indian producer, Filatex, says it's now paying nearly 30% more for its key raw materials.
That's why in Surat's weaving district, many looms have gone quiet.
At Radheshyam Textile, half of the 200 looms sit idle.
Kaushik Dudhat is the owner.
"Before the war, we used to produce at least 11,000 yards of polyester fabric per day, which has come down to 3,800 to 4,300 yards, because if we want to produce more, we will have to purchase more raw materials and we will not be able to buy it at the present rates as the finished fabric will not be sold at a profitable rate that can benefit us."
Research group Wood Mackenzie says Indian prices for the fiber rose by around a quarter over the month from late February.
For now, some retailers will be protected from that by earlier purchases and the use of recycled polyester.
Clothing giant H&M said it hadn't seen any big impact yet.
But if factory prices stay high, shoppers could soon find their fast fashion getting more expensive.
