France lost to Argentina on penalties, failing to defend their crown picked up in 2018.
Mbappe, though, had an excellent tournament. He scored seven goals to win the Golden Boot.
He also became the second player in history to score a hat-trick in a World Cup final.
The 23-year-old, who is already just four goals behind all-time leading World Cup finals scorer Miroslav Klose with 12 in 14 games, did not conduct any post-match media duties after such an agonising loss on sport’s biggest stage.
That silence continued into Monday morning, but Mbappe has now commented publicly on the gut-wrenching defeat with an ominous short tweet that should strike fear into every international defender the world over.
“Nous reviendrons [we will return],” he said simply.
Given Mbappe is still only 23, he will have at least two more chances to lift the World Cup, the next coming in 2026 where France will once again be amongst the favourites.