During the trip, which has also taken him to Guatemala, Honduras, El Salvador and Belize, Lopez Obrador urged the United States – where many migrants are headed – to help solve underlying economic problems fueling the wave, AFP reported.
Cuba has seen its own exodus accelerate, with more than 78,000 of its nationals arriving in the US via Mexico from October 2021 to March this year, according to US customs data.
The wave has been fueled by the communist nation's worst economic crisis in nearly three decades, which it blames in large part on six decades of US sanctions that were tightened under Donald Trump.
On Sunday, Lopez Obrador said he would continue to insist that the United States lift what he called a blockade against the island nation.
Many thousands of US-bound undocumented migrants, most of them Central Americans, cross Mexico's southern frontier with Guatemala each year fleeing poverty and violence.
In 2021 alone, Mexican authorities detected more than 300,000 irregular migrants.
US Customs and Border Protection officials have registered 7,800 undocumented migrants a day along the border with Mexico in recent weeks – almost five times the average in 2014-2019.
Lopez Obrador argued on his trip that migration from Latin America was "the result of the difficult conditions in our countries, from the Rio Grande to the south."
"The will of Latin Americans is not enough; we also need the United States to become clearly involved in solving a problem that also affects it and to contribute to financing job creation projects," he said in Honduras.
Lopez Obrador arrived in Havana on Saturday on the heels of an explosion at a luxury hotel in the city center that killed at least 30 people.
His visit marks 120 years of diplomatic relations with Cuba. Mexico is the only Latin American country not to join the global effort to isolate Fidel Castro's government in the 1960s, instead maintaining trade with Havana.