DUBAI (Reuters) - Saudi Arabian Mining Co (Ma’aden) (>> Saudi Arabian Mining Company (Ma'aden)), the Gulf's largest mining company, has asked banks to submit proposals for a loan which would refinance some $2.88 billion of existing debt, sources familiar with the matter said on Wednesday.

It sent a request for proposals to banks last week and the banks have until the end of September to respond, the sources said.

The facility would be the largest corporate loan out of Saudi Arabia since 2015, according to Thomson Reuters data.

The state-controlled miner is raising the financing for Ma'aden Aluminium, an integrated aluminium facility. France's BNP Paribas and Saudi Arabia's National Commercial Bank are coordinating the fundraising, which could be completed by the end of the year, one of the sources said.

Ma'aden and BNP Paribas declined to comment, while NCB did not respond to requests for comment.

Ma'aden raised the original financing for its aluminium project, a joint venture between Ma'aden and U.S. aluminium giant Alcoa (>> Alcoa Corp), in 2010.

At that time the company obtained a $1.9 billion loan from 16 financial institutions to back Ma'aden Aluminium Co and Ma'aden Rolling Co, both owned by Ma'aden with 74.9 percent stakes and Alcoa with 25.1 percent.

In December of that same year, Ma'aden also obtained a $2.12 billion loan from the Saudi Arabian government's Public Investment Fund to finance the first phase of the project.

The loan that Ma'aden is now seeking would refinance the aluminium company's entire commercial debt, one of the sources said. It would be denominated in both U.S. dollars and Saudi riyals, and have tenors of seven and 10 years.

The company has approached both local and international banks for the loan, which would be closer to a corporate finance facility than to the original project financing arrangement, the same source added.

The aluminium project will eventually become the largest aluminium complex in the world, employing more than 3,000 people, according to Ma'aden.

Under reform plans designed to diversify the economy beyond oil exports, the Saudi government plans to more than triple the mining industry's contribution to gross domestic product by 2030, making Ma'aden a major player in the reforms.

(Editing by Andrew Torchia and Louise Heavens)

By Davide Barbuscia and Katie Paul

Stocks treated in this article : Saudi Arabian Mining Company (Ma'aden), Alcoa Corp