On 7 October 2026, a constitutional reform came into force in Mexico that prohibits candidates for president, state governors and the mayor of Mexico City from holding dual citizenship.
The reform was proposed by President Claudia Sheinbaum at the end of August and quickly passed through Congress with the support of the ruling Morena party and its allies.
Under the changes, contenders for these offices must be Mexicans by birth and must not have, or acquire, any other nationality. If they already hold one, they must formally renounce it before registering their candidacy.
Sheinbaum signed the decree and stated: "Today we signed the decree... Neither the president nor a governor may hold dual citizenship."
The new rules will take effect from 2028, so the 2027 elections will be held without changes, and incumbent governors are not affected.
The president explained the initiative by the need to protect the country from foreign interference: "Mexico's presidents can have only one flag, one homeland, one people to defend."
Opponents believe the reform violates the rights of Mexicans who emigrated abroad and obtained, for example, US citizenship, and note that the Constitution already contains nationality requirements for the highest offices.
Critics also point out that the amendments may be aimed at limiting opposition candidates, including those with ties to other countries.
In Latin America, similar restrictions are already in force in Cuba, Nicaragua and Venezuela.
The reform amends Articles 82, 116 and 122 of the Constitution and requires candidates not only to renounce a second citizenship but also to refrain from using foreign passports or seeking diplomatic protection from other states while in office.
How will this affect the country's political landscape in the long term?
The next presidential election will be held in 2030, and by then all contenders will have to meet the new requirements.
