KoBold Metals Co. has reached a preliminary agreement to move forward with the development of one of the world’s biggest hard rock lithium deposits in the Democratic Republic of Congo.

The firm, backed by billionaires Bill Gates and Jeff Bezos, reached a framework agreement with Australia’s AVZ Minerals Ltd. to buy the latter’s stake in project on the Manono deposit, according to a letter signed by KoBold Chief Executive Officer Kurt House and his AVZ counterpart Nigel Ferguson.

“The agreement will enable KoBold to rapidly deploy more than $1 billion to bring the Manono lithium to Western markets,” said the companies, which are working on the arrangement with the US and Congolese governments.

The announcement comes after Congo’s President Felix Tshisekedi met with Massad Boulos, US President Donald Trump’s senior adviser for Africa, to discuss potential American investment and security assistance in Congo’s fight against a Rwanda-backed rebel group.

Tshisekedi is hoping US interest in Congo’s minerals will encourage the Trump administration to back his government, which is teetering amid the rebel advance in the east. Besides lithium, the central African nation is the world’s second-largest source of copper and biggest producer of the electric-vehicle battery metal cobalt.

Any final deal for the lithium around the southeastern town of Manono will require the resolution of multiple arbitration cases surrounding the deposits. AVZ was close to breaking ground on mine construction when Congo canceled its rights in 2023 and split the permit, handing part to China’s Zijin Mining Group Co.

AVZ is willing to suspend the arbitration proceedings to “facilitate discussions” between the parties, the two CEOs said in the letter. Congo will need to return the license containing the southern section of the Manono project to KoBold for the development to proceed.

KoBold has proposed a plan that would see AVZ receive compensation, while Zijin continues developing a mine in the northern portion of the Manono deposit, according to another letter addressed to Tshisekedi’s office in January and seen by Bloomberg. Rio Tinto Group has also held talks with Congo and KoBold about investing in the project.

Spokespeople for Congo’s presidency and mines ministry didn’t immediately respond to questions seeking comment on the agreement between AVZ and KoBold.

AVZ said in 2020 it intended to build a mine at Manono capable of producing about 700,000 tons of lithium concentrate a year for two decades. That would the biggest operation of its kind outside Australia.

Michael Bloomberg, the majority owner of Bloomberg News’s parent Bloomberg LP, is an investor in Gates’ Breakthrough Energy, which holds a stake in KoBold, according to the company’s website.