HONG KONG — The latest OpenAI chatbot has proved a hit among tech-savvy Chinese in the past week even though the service is officially unavailable for users in the country and requires a foreign phone number to register.

ChatGPT, which answers user questions, is a project from OpenAI, a San Francisco-based artificial intelligence (AI) research lab founded in 2015 by a group of individuals and organisations, including current CEO Sam Altman. Tesla’s Elon Musk was also among the early founders.