The 39-year-old wrote the message on 21 July, two days after Argentina's extra-time defeat by Spain in this summer's World Cup final, but held off publishing it while his father Jorge's health worsened. Jorge Messi passed away on 8 August at a hospital in Rosario, aged 68, following a long illness.
"Today, after what happened with my dad, I'm even more convinced than before," Messi added on Instagram on Monday. In the statement itself, he wrote: "Time is running short, chapters come to a close, and this is one that hurts me deeply. I love, have loved, and will always love being part of the national team.
"I've given it my all, I have nothing left to give, and besides, there are some really great young players coming through behind me who deserve their chance."
Messi leaves international football as Argentina's all-time leading scorer and most-capped player, with 125 goals in 207 appearances across two decades. He captained the side to World Cup glory in Qatar in 2022 — the country's first title in 36 years — and added two Copa America triumphs either side of it, before this summer's run to a second World Cup final, in which he scored eight goals and added four assists. His 12 career World Cup assists, 10 of them in knockout matches, is a record no other player has matched.
The eight-time Ballon d'Or winner is the second-highest scorer in World Cup history with 21 goals, one behind France's Kylian Mbappé, and sits second on the all-time list for international goals behind his longtime rival Cristiano Ronaldo, who has 146 for Portugal.
It is a strikingly different ending to a debut that suggested anything but greatness. Messi came on as a 63rd-minute substitute against Hungary in Budapest in August 2005 and was sent off less than a minute later, after his elbow caught defender Vilmos Vanczák as he tried to shake off a shirt-pull. He first retired from international duty in 2016 after missing a penalty as Argentina lost to Chile in the Copa America final, reversing the decision within weeks.
Tributes poured in following Monday's announcement. Messi's wife, Antonela Roccuzzo, addressed him directly on Instagram: "I was also lucky enough to see you fulfil your dreams and live some of the happiest days of our lives. You deserved this story and so much more."
FIFA president Gianni Infantino, meanwhile, praised a career that "has inspired millions of people and redefined our sport."
"Thank you for all the love over the past 20 years," Messi told supporters. "I'm going to miss hearing you from the pitch so much. Now I'll be just one of you, always cheering and supporting from the sidelines. I'm leaving with the peace of mind and pride of having given you, together with my team-mates, moments we'd only dreamed of. It was incredible to have experienced this with you all. I love you!"
His playing career continues at club level with Inter Miami, where his Major League Soccer contract runs to the end of the 2028 season.