After stepping away from the company in 2019, Google co-founder Sergey Brin recently returned to the tech giant to work in-person and he’s now asking all workers to consider doing the same.

According to an internal document viewed by the firm, Sergey Brin, co-founder of Google and board member of Alphabet (GOOGL, Financials), advised staff members at DeepMind, the artificial intelligence branch,

Brin has urged those working on the Gemini AI models to commit to 60-hour workweeks and come to the office every weekday. This statement comes at a time of intense competition in the AI sector, accelerated by the rapid surge of OpenAI’s ChatGPT.