Maaden said in March that it plans to add a new production line, with a capacity of 100,000 tons per year, at its aluminum joint venture with US firm Alcoa to produce sheets used in the automotive and construction industries.
It said that financing for the project will be announced at a later date.
"It is a SR7 billion loan for five years," the banker, who declined to be named, said, adding that the loan will be finalized by the third quarter of this year.
HSBC Saudi Arabia, an affiliate of HSBC, will be the lead arranger, he said.
A spokesman for Maaden could not immediately comment.
The aluminum complex is owned 74.9 percent by Maaden and 25.1 percent by Alcoa.
In February Maaden said it plans to invest SR21 billion in a phosphate project as part of a new industrial city in the country's north.
