OpenAI chief executive Sam Altman is stepping down as chair of advanced nuclear reactor developer Oklo to avoid a conflict of interest ahead of talks between his company and the nuclear startup on an energy supply agreement.

Altman, who was an early-stage investor in US-based Oklo, will step down immediately and be replaced by Jacob DeWitte, the group’s chief executive officer and co-founder.

The move gives Oklo more flexibility to potentially explore partnerships with OpenAI or other cloud service providers amid data centre companies’ push to secure power.