"All too often we're hearing rhetoric that ignores the enormous contributions that have been made by Mexican Americans and the enormous strengths we draw from the relationship," Obama said, without naming the Republican billionaire who hopes to succeed him as president.
At the start of the so-called "Three Amigos" summit hosted by Canadian Prime Minister Justin Trudeau, Mexican President Enrique Pena Nieto offered a clear warning: "Isolationism is not a road towards progress," he said.
Yesterday, Trudeau urged people to resist the temptation of "turning inward," warning of the high economic cost for nations that choose to go it alone.
Trump has promised to build a wall on the US border with Mexico to stem the flow of illegal migrants into the United States, and rails regularly against the North American Free Trade Agreement (NAFTA) signed by his rival Hillary Clinton's husband Bill when he was president.
In a speech in Pennsylvania yesterday, Trump said he intended to renegotiate the 1994 accord that unites 530 million consumers and represents more than one-quarter of the world's gross domestic product (GDP).
While arguing for greater North American integration as the key to the continent's economic prosperity, Trudeau also warned of a growing backlash against globalization and rising protectionism.
The three nations at the Ottawa summit also announced a collaborative strengthening of their efforts to fight climate change.
The aim is to produce 50 per cent of the continent's overall electricity from "clean energy," including from solar and wind, nuclear and hydroelectric generation, by 2025.
"The Paris Agreement was a turning point for our planet, representing unprecedented accord on the urgent need to take action to combat climate change through innovation and deployment of low-carbon solutions," the leaders said in a joint statement calling for the accord to come into force before the end of the year.
