This despite a disappointing 0-0 draw with Fiorentina on Saturday.
He said, “Anyone who doesn't believe in the Scudetto should stay out of the locker room. As long as it is mathematically possible, I will continue to believe.
“We are very competitive and want to get closer to Juve. It's tough, because they are strong and keep winning, but we have to continue along our path."
Koulibaly added, “It's disappointing, as Fiorentina caused us problems with their high press in the first half, but once we started passing it around well, we went clear on goal several times."