Mr. Diamond, 62, is raising money for a $250 million vehicle that would invest in the banking business in Africa. The corporate shell, known as Atlas Mara, would list in the coming weeks on the London Stock Exchange, according to people briefed on the matter.
The American executive is teaming up with Ashish J. Thakkar, 32, an entrepreneur whose Mara Group conglomerate has technology, manufacturing and real estate operations and interests in 19 African countries. Mr. Thakkar began his career by setting up a technology business in Uganda at age 15. (The name of the cash-shell vehicle reflects the conglomerate and Atlas Merchant Capital, a merchant bank Mr. Diamond has founded.