The 23-year-old midfielder was part of Didier Deschamps' initial France squad for the World Cup in Brazil, but was ruled out prior to the tournament after pulling up with a groin injury in training.
Grenier made 28 Ligue 1 appearances for Lyon last season, scoring four times as the side finished fifth under the stewardship of Remi Garde.
Garde has since moved on, to be replaced by Hubert Fournier, and Grenier has been heavily linked with a move to Premier League Newcastle.
Amid suggestions he had purposefully missed training in order to prompt a move to England, Grenier took to his official website to dispel any such claims, explaining that he had undergone specialised training in order to recover from his troublesome groin problem.
"I have no problem with the club and have never missed a training session intentionally," he said.
"There is no controversy and my intention is to be back on the pitch and competing as soon as possible.
"To put things into context, I just want to make everyone understand that an individualised programme has been implemented in accordance with the medical staff and technical staff of the OL so I can return to 100 per cent of my abilities.
"This requires a suitable recovery period with a lot of individual work and muscle building that takes place indoors.
"This is why I am not present at certain meetings with the rest of the group."
