French under-21 international midfielder Christopher Nkunku has joined RB Leipzig from Paris Sain-Germain, the Bundesliga club announced on Thursday.
The transfer fee is around €13 million ($14.6 million) plus two additional payments, according to media reports.
Leipzig said Nkunku had signed a five-year contract.
"Christopher Nkunku has the qualities we were looking for," said Markus Kroesche, RB Leipzig's sports director. "He is a dynamic player who can play in several positions and offers us several possibilities to vary our game."
The 21-year-old attacking midfielder came through the PSG youth system and since making his debut in December 2015 has made 78 appearances scoring 11 times. He appeared in 22 Ligue 1 matches last season, starting 13 times, but did not play in the Champions League.
"I am looking forward to wearing the RB Leipzig jersey. I am convinced that the club's style of play suits me very well," said Nkunku.
Although skilful and capable of dazzling play, Nkunku has often been erratic and PSG need to balance their books to meet Financial Fair Play regulations.
Leipzig already have two other young Frech players, 20-year-old defender Dayot Upamecano and another PSG youth product, 22-year-old striker Jean-Kevin Augustin.