leaders of canada and mexico. the record-breaking surge of migrants along with how to better secure the u.s. southern border is a major focus. also on the agenda, trade, economic issue, climate change and the renewed efforts to combat the flow of illegal drugs into the u.s. from mexico. cnn s priscilla alvarez in is mexico city. what are the big takeaways so far? reporter: well, so far all the leaders have been reaffirming their strong relationship but it s a rubber hits the road moment when talking about what the commitments are going to be moving forward on this range of issues and first and foremost migration. this is an issue that all three countries have to wrestle with as there is unprecedented mass movement in the western hemisphere and the white house has been quite clear for months now that they expect that regional partners have to work together to stem the flow of migration, an issue that has become a political vulnerability for president biden on the u.s./mexi