Mane wants his fellow compatriots to make a transfer move to Liverpool this summer, adding that he would be very happy to play alongside him at club level.
The former Southampton star knows Koulibaly well after having played alongside him for a number of years for the Senegal national team.
Koulibaly, 29, has been linked with a move away from Napoli to Liverpool, Manchester United, Tottenham, Arsenal and PSG in the past.
“Kalidou Koulibaly is an excellent defender, and one of the world’s best in his position,” The Sun UK quoted Mane as saying.
“I would be very happy to play alongside him at club level, as I have known him for years.”
Mane added: “We first got to know one another at Metz before meeting up once more in the Senegal national team.
“No club could refuse the chance to have Koulibaly in their squad.
“In any event, it would be a pleasure for me to play for Liverpool together with him.
“He would be more than welcome here.”
