France boss Fabien Galthie said his team "lost control" against England as Maro Itoje's late try allowed the hosts to snatch a 23-20 victory at Twickenham.
In a sizzling Six Nations match, France went ahead through Antoine Dupont after just 65 seconds and led 20-13 early in the second half.
They were looking like earning a first victory in the championship in London since 2005 until England came back strongly in the closing stages.
Itoje crossed in the 76th minute, with a TMO verdict showing he had just managed to ground the ball.
Galthie told broadcaster France 2: "In the second period, we lost control of the match. We backed off. We held the line until Maro Itoje scored.
"The English ended up stronger, they managed to occupy the field more than we did. The team had a big game.
"We were ahead until three minutes from the end, but that's not enough."
France had won their opening two matches before a COVID-19 outbreak in the squad caused the clash with Scotland to be postponed.
Talk of a Grand Slam would have abounded had they held on against England, but it was not to be.
Galthie added in a news conference: "The two teams delivered a great match, before a denouement that must be digested.
"It played out once again in the final minutes. But above all, I am proud of my players, of their solidarity.
"It's a game that makes you grow. We didn't win but they felt we could win it. There are two, three key moments that perhaps would have allowed us to finish it more comfortably.
"In the end, the English dispossessed us of the ball because we conceded penalties, lost balls. But that's good. The team learns."
France face Grand Slam-chasing Wales next Saturday in Paris, knowing a victory over the Red Dragons would keep hopes alive of winning the championship.
Galthie added, according to Le Figaro, that France would react "by keeping the positives".
"We will digest this result together and switch to Wales now," he said. "That match starts right away. It depends on our ability to share and experience together the frustration to plan for the match that awaits us next Saturday."