This handout picture released by the Mexican Presidency shows Mexico's President Andres Manuel Lopez Obrador speaking during a press conference in Mexico City on March 28, 2023. (PHOTO / MEXICAN PRESIDENCY / AFP)

MEXICO CITY – Mexican President Andres Manuel Lopez Obrador is receiving medical treatment and self-isolating after testing positive for COVID-19, the country's Interior Minister Adan Augusto said Monday in a morning press conference.

Augusto said that Lopez Obrador was at the presidential headquarters and that the president had shown cold-like symptoms since Saturday. He denied a media report that the president had suffered a heart attack.

Later that day, the president said he had tested positive for COVID-19, and wrote on his official Twitter account that "My heart is at 100%"

On Sunday, local newspaper Diario de Yucatan reported that Lopez Obrador had suffered an apparent heart attack while on a trip to the Yucatan Peninsula, helping to fuel rumors about the President's health which circulated widely on social media.

Later that day, the president said he had tested positive for COVID-19. "It's not serious," he wrote on his official Twitter account. "My heart is at 100%."

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This is the third known COVID-19 diagnosis for Lopez Obrador, 69, who had a serious heart attack in 2013. He reported mild symptoms from both of his previous bouts of COVID-19 at the height of the pandemic.