The 25-year-old forward made his U.S. debut in a Jan. 25 exhibition against Serbia but remained eligible to ask FIFA for a one-time switch of affiliation to Mexico.
"I am excited for this next chapter, and earning my place with the USMNT," Zendejas said. "Thank you to everyone for the incredible support."
The announcement concludes a bizarre tug-of-war between the U.S. and Mexico, one in which Zendejas initially played for the U.S. at the youth level, including at the 2015 FIFA U-17 World Cup, where he was a teammate of Christian Pulisic and Tyler Adams.
But upon joining Liga MX side Chivas in 2016, Zendejas said he would reject future U.S. call-ups and would play for Mexico.
But Zendejas never filed the required one-time switch with FIFA to become eligible to play for Mexico, which was necessary because he had played for the U.S. in official competition.
Mexico was ordered to forfeit five matches (three at the youth level) and fined 10,000 Swiss francs ($10,900) by FIFA for using Zendejas while he was affiliated with the United States.
That development saw Zendejas return to the U.S. fold, and he played in the January friendly earlier this year against Serbia.
Now he will be available to play for the U.S. in the CONCACAF Nations League games later this month.
"I am very proud of being Mexican-American. Values from both cultures have made me the person I am today," Zendejas said in a statement Tuesday. "Making a decision on your international career is very difficult, and I believe in following your heart. Mine tells me that my future lies representing the USA."
Zendejas was born in Ciudad Juarez, Mexico, but was raised in El Paso, Texas. He is a product of the FC Dallas Academy, and he made his team debut with the club in 2015.
He made his MLS debut against Houston on May 1, 2015, and transferred to Chivas in June 2016, then went on loan to Zacatepec in June 2017. Zendejas transferred to Necaxa in June 2020 and to Club America in January 2022.
His aforementioned move to Chivas saw him struggle for playing time, but the loan to Zacatepec saw Zendejas find his footing in the pro game, and he eventually moved to Necaxa on a free transfer.
After scoring 11 goals in 50 league matches, Zendejas moved to Club America in January 2022. He has been a steady and at times spectacular contributor for the Aguilas, scoring 13 goals in 43 league matches.
In terms of the USMNT, Zendejas will provide additional depth at the wing positions, but he faces stiff competition from the likes of Chelsea's Christian Pulisic, Borussia Dortmund's Giovanni Reyna, Leeds United's Brenden Aaronson and Lille's Timothy Weah.