Didier Deschamps's side head into tomorrow's clash in Brasilia as clear favourites to beat the Super Eagles en route to sealing a quarter-final spot.
However, the African nation pushed Argentina all the way in a thrilling 3-2 defeat to the South Americans earlier this week, and the Arsenal defender is well aware that Les Blues have a game on their hands.
"The first objective was to get through the group phase. Now it's to go as far as possible," he told FIFA.com.
"We are competitors and we are ambitious, but we know that we have opponents against us and that we might lose.
"We're aware of our qualities, but anything is possible in a knockout match and for the moment we're only focusing on the last 16."
Tomorrow's encounter kicks off at 5pm.