Loosehead prop Poirot, who started just one of les Bleus matches during this year’s Six Nations, led his country against Tonga in the group stages of the competition before the last-eight loss to Wales.
“When the competition finished, a few minutes after the final whistle, I felt empty. The decision was made in a fraction of a second,” he told newspaper L’Equipe.
“I feel my motivation is not at its maximum. I always promised myself I would be at 100 per cent when playing for France, to not lie. Les Bleus, it’s the Holy Grail. I can’t go and play for them and just take my cap and my bonus,” he added.
The Bordeaux-Begles front-rower lost his starting Test place to Cyril Baille for the Six Nations was dropped from the squad later in the campaign.
“It’s not in my character to give up. Taking this decision is much deeper than that,” Poirot said.
“It was difficult but it had the contrary effect. It made me feel relief. The decision was even easier to make. I might be criticised, but I haven’t lied to anyone,” he added.
Poirot was among the favourites to replace retired Guilhem Guirado as full-time les Blues captain after the World Cup but new head coach Fabien Galthie chose flanker Charles Ollivon as his skipper.
“I would have been in a trap. I couldn’t have retired. The captaincy is a heavy responsibility. In the state I was in it would have been horrible to take over the role,” Poirot said.
“Not being named captain gave me freedom. Finally it was a relief. It’s sad and powerful to say that, but it’s the truth,” he added.
The former Brive forward said even France hosting the 2023 World Cup did not sway his choice.
“It will be an enormous event. I hope les Bleus will be world champions. But it never crossed my mind in my decision,” he said.
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