"We were not as good in the first 60 minutes against top-quality opponents who had a lot more energy, but we came back from nowhere and turned the game around from a very difficult situation. That leaves us with even more regrets," said Deschamps after France failed in their bid to become the first team in 60 years to retain the trophy.
Kylian Mbappe scored twice in two minutes late on in Doha to cancel out Argentina's two-goal lead and force extra time, in which he scored again from a penalty to complete his hat-trick and make it 3-3 after Lionel Messi had put the opposition back in front.
Randal Kolo Muani was then denied a last-gasp winner by goalkeeper Emiliano Martinez, and Argentina won the shoot-out 4-2, with France's Kingsley Coman seeing his penalty saved and Aurelien Tchouameni missing the target.
"We had a chance to win the World Cup in the last minute but it wasn't to be," Deschamps said.
"At 2-0 there would not have been the same regrets, you just say 'bravo' to them.
"I don't want to take any merit away from Argentina but there were lots and lots of emotions and it was cruel at the end because we were so close."
Deschamps suggested that the virus which laid low several of his players in the run-up to the final was partly to blame for their poor performance over the first hour.
"There were many reasons which explained why we were not as good. Several important players had less energy but bringing on younger players with less experience but plenty of freshness and quality allowed us to keep dreaming.
"But unfortunately the dream did not come true."
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