Messi found the back of the net for the seventh time in Qatar, only for Mbappe to equalise again as the final went to penalties.
Both scored in the shootout but Kingsley Coman and Aurelien Tchouameni were then unable to convert their spot-kicks, before Gonzalo Montiel gave Argentina a 4-2 win on penalties after it finished 3-3 at the end of 120 minutes.
Speaking after the match, Messi insisted the game would not be his final international game.
“No, I’m not gonna retire from the national team,” Messi told TyC Sports.
“I want to keep playing as World Cup champions with the Argentina shirt.”
On lifting the World Cup, he added: “I knew that God was going to give it to me.”
The World Cup win is Argentina’s first trophy since Diego Maradona led them to glory in 1986, and it comes 18 months on from the Copa America triumph. Messi now has his defining moment, fulfilling a destiny that appeared increasingly inevitable as the tournament went on.
