I think the ones with these countries are too new to say. The NAFTA one is the longest standing one.
There's the Commission for Environmental Cooperation that was set up with Mexico, Canada, and the United States. There are some useful mechanisms there. For example, when there's tri-country reporting on the level of pollution by the biggest polluters in the three countries, it's been useful for the three countries to see a joint report where they see who are the biggest polluters, in which country. The embarrassment factor that results can be useful.