The managing director of Bandar Abbas Gas Condensate Refinery, also known as Persian Gulf Star Refinery, said the project would need over a billion dollars in fresh investments for completion.
Morteza Emami said the money will be procured through various methods including dipping into the National Development Fund of Iran.
He said attracting more investments by the project's stockholders, product-sales contracts and financing are other methods considered for procuring the cash.
The official said talks are under way with a number of investors from Europe and Asia under Off Take and Direct deals.
"Foreign investors demand certain guarantees which we cannot provide for them, he added.
The refinery, Iran's largest gas condensate refining facility, supplies 8 million liters of euro-4 petrol on a daily basis which will cross 10 ml/y once the plant's isomerization unit is operational soon.