As Mexico begins the process of transition to a new administration, there is considerable doubt about the true nature of the new president, Andres Manual Lopez Obrador, or AMLO as he is commonly known.

AMLO won Sunday’s election with an extraordinary 53 percent of the vote, giving him a clear mandate. Throughout his career, he has taken strong stances on topics like corruption, on what he calls “the mafia in power,” and on poverty and inequality. As a result, he is a figure that inspires hope or fear, dividing Mexicans neatly down the middle.

In the United States, AMLO has drawn a similar reaction, with many worrying about the future of the bilateral relationship. Of particular concern is the future of cooperation on migration. It is a topic that will likely lead to some tensions between the Trump administration and the new government, who will likely re-evaluate its alignment with the United States on topics regarding Central American migration and Mexican emigration to the United States.

Given the controversial nature of the issue and its importance for President Trump, the future of the Mexico and U.S. relationship might just depend on how willing each leader is to work on migration.

AMLO’s platform has focused on combatting corruption and working on poverty reduction, prioritizing his attention to the development of Mexico’s poorer areas. He is calling for drastic reforms to improve conditions for poorer Mexicans, such as increased social spending.

In line with this, his migration agenda wants to tackle the root causes of migration, like economic deprivation, and largely focuses on keeping Mexicans in Mexico. He states, “People want to live where their families, their customs, their traditions and their culture are from. If people want to emigrate, let it be by choice not necessity.”

For Mexicans in the United States, AMLO has proposed a 5-Step Plan to provide support abroad. The plan will turn the 50 Mexican consulates in the United States into “advocates” for the defense of Mexican migrants.

Placing Mexicans residing in the United States at the forefront of his migration policies is a smart move. Historically they have played a vital role in defending migrant rights, and in providing services and support to Mexicans abroad. Mexico has 50 consulates in the United States, covering almost all of the national territory. AMLO wants to improve and increase their capacity to engage more fully with this migrant population

The migration crisis from Central America is also an area ripe for disagreement between Trump and AMLO. Current Mexican President Enrique Pena Nieto is mostly aligned with U.S. interests, militarizing Mexico’s southern border to stem migratory flows from Central America. Mexico is the first line of defense to prevent migrants and asylum seekers from reaching the United States, so the United States poured hundreds of thousands of dollars to fund Mexico’s Southern Border Program. Furthermore as Mexican migration flows decrease, Central American migration will continue grow in importance.

AMLO has strongly condemned the separation of Central American families, calling the practice racist and inhumane. He has spoken of his desire to treat migration as a human right. AMLO’s nominee for secretary of the interior, Olga Sanchez Cordero, said they would craft a migration policy that respects and upholds the human rights of Central American migrants.

AMLO himself has stated, “We criticize Trump, but we (Mexico) do the same thing with the Central American migrants.”

Obrador himself is from the state of Tabasco on Mexico’s southern border, where the majority of migrants cross through to either settle in Mexico, or begin the perilous journey across Mexico to the United States.

It is no secret that President Trump has projected strong rhetoric against Mexico and Mexicans. AMLO has also spoken out on multiple occasions against the president, even publishing a book called “Listen Up, Trump,” in which he stated the president was xenophobic and Nazi-like in his rhetoric about Mexicans. He has also come out against funding a border wall and advocated for Mexico to move away from taking a deferential stance to U.S. interests. AMLO has pushed for Mexico to take a stronger leadership stance with less reliance on the United States.

Yet, criticism of Trump may not result in conflict. In his book and in a few speeches, AMLO speaks about the importance of a robust U.S./Mexico relationship. He has stated he will have patience with Trump and seeks a relationship based on mutual respect. It is difficult to guarantee diplomatic rhetoric from the U.S. president, but his tweet to the Mexican president-elect was congratulatory and respectful, and subsequent phone call to discuss trade and immigration opens up a window of opportunity for future discussions.

If the mutual respect AMLO seeks does not occur, the relationship could be one of cold shoulders and an increasingly “Mexico First” attitude, that will focus less on foreign policy and bilateral cooperation, and more on Mexicans in Mexico and the Mexican diaspora in the United States.

There is no denying that a bilateral relationship between the United States and Mexico is vitally important to both sides; but there are many opportunities for it to hit the rocks. Migration might just be the issue that tilts the balance one way or the other.