SoftBank is in talks to invest $15 billion to $25 billion in OpenAI, potentially deepening the relationship between the two companies that are already planning a significant artificial-intelligence infrastructure initiative.

Some of that equity investment could be used for OpenAI’s commitment to Stargate, a joint venture with SoftBank and others it announced last week at the White House, according to a person familiar with the matter. Stargate, which also includes Oracle and the United Arab Emirates investment fund MGX, intends to invest as much as $500 billion in AI data centers for use by OpenAI over the next four years.