Mexican President Claudia Sheinbaum signed a constitutional amendment requiring future candidates for the presidency, state governorships and Mexico City’s head of government to hold only Mexican nationality.
Sheinbaum signed the decree on the event date of October 7, 2026, after approval by the federal Congress and a majority of state legislatures. The measure was scheduled for publication in the government’s official gazette, completing the formal process for the constitutional change.
Although the decree takes effect legally upon publication, the new eligibility rule will apply from 2028. It therefore will not affect elections scheduled for 2027. Prospective candidates who hold another citizenship would have to renounce it before seeking one of the offices covered by the amendment.
Sheinbaum proposed the change in late August and defended it as protection against foreign interference. Her governing Morena party and its allies supplied the majorities in both chambers of Congress, while enough local legislatures also approved the amendment to satisfy the requirements for changing the constitution.
Supporters argued that existing constitutional provisions concerning nationality left ambiguity around eligibility for senior executive office. The new wording makes the restriction explicit for presidents, governors and the head of the capital’s government.
Opponents say the measure limits political rights and disproportionately affects Mexicans abroad, many of whom also hold citizenship in the countries where they live. The conservative National Action Party argued during debate that the rule penalizes millions of emigrants while leaving legislators free to possess another nationality. It also disputed the idea that the number of passports a person holds reliably indicates national loyalty.
Larry Rubin, president of the American Society of Mexico and a dual citizen of Mexico and the United States, also criticized the proposal. He argued that loyalty should be judged through conduct, a person’s record and adherence to the constitution, rather than citizenship count.
The reform places Mexico among a group of Latin American countries that expressly bar presidents from holding another nationality. However, its reach beyond the presidency to governors and Mexico City’s leadership gives it a broad effect across executive politics.
The delayed 2028 application provides time for electoral authorities and potential candidates to interpret and comply with the requirement. It also means the first practical consequences will emerge after the next round of voting, even though the constitutional text is now in place.
Debate is likely to continue around the balance between preventing foreign influence and preserving the political participation of Mexico’s large diaspora. For now, the amendment establishes a clear new condition: contenders for the country’s most powerful executive posts must possess Mexican nationality alone.
