The 23-year-old is set to join Lyon on a four-year contract.
“We are on the way to having a new recruit,” Garde told the club’s official website.
“The unavailability of John Mensah and Cris has rushed things a little but Kone is a player we had targeted, who we followed for some time.
“I myself have seen many videos of him. This is a player who has potential and room for improvement.”
