Argentina World Cup-winning captain Lionel Messi says he has no idea when he will finally call time on his international career.

"Even I don't know when. It'll happen when it happens," the 36-year-old said in an interview broadcast on Argentine television on Wednesday.

"After winning everything I want to enjoy the moment and wait for time to tell me when it's the moment," said the seven-time Ballon d'Or winner.

"Logically, given my age, one would expect it to be soon, but I don't know for sure.

"Now that we are American champions (Argentina won the 2021 Copa America) and world champions we have to enjoy that."

He reiterated earlier comments that he was unlikely to be in Argentina's squad when it defends its World Cup title in 2026.

The interview was conducted in China last month, when Messi scored the quickest goal of his career after just 79 seconds in a 2-0 friendly win against Australia in Beijing.

On Tuesday, Messi arrived in Florida to put the final touches on his move to Major League Soccer club Inter Miami from Paris Saint-Germain.

He is expected to put pen to paper on a two-and-a-half-year deal, reportedly worth $60 million a year, before being presented to fans at a stadium event on Sunday.

AFP