These are tricky issues. :)

AI research seems to correspond with a prisoner's dilemma, so I wouldn't expect cooperation.

Fortunately, many real-world scenarios are iterated prisoner's dilemmas (e.g., moving ahead with your country's AI research faster than what was agreed upon). We can also set up side payments against defection, such as by an international governing body. And changing people's views about the payoffs (such as by encouraging an internationalist outlook) could make the game no longer a prisoner's dilemma.

In general, this highlights the importance of improving theory of, institutions for, and inclinations toward compromise.