Nkunku is one of the rising stars of European football and scored 23 goals in 36 games for Leipzig last season.
He is the first major signing since Mauricio Pochettino was confirmed as Chelsea’s new manager at the end of May.
“I am incredibly happy to be joining Chelsea. A big effort was made to bring me to the club,” Nkunku said.
– ‘Creativity and versatility’ –
Laurence Stewart and Paul Winstanley, Chelsea’s co-sporting directors, said: “Christopher has proved himself one of the standout attacking players in European football over the past two seasons and will add quality, creativity and versatility to our squad.”
Nkunku earned his France debut last year and has been capped 10 times.
He was ruled out of the 2022 World Cup in Qatar with a leg injury.
“I am very excited for this challenge and will be proud to wear the Chelsea shirt.”
Bidding farewell to Leipzig, Nkunku wrote a heartfelt message on the club’s website:
“Now it’s time for me to say ‘Au Revoir’ Leipzig. I am incredibly grateful to RB Leipzig and everyone at the club – my team, the coaching staff, the staff and most importantly the fans. I had four years in Leipzig which I will never forget,” he said.
“I represented my country while at RB Leipzig, I have developed extremely well from a sporting and personal perspective and we have now been able to crown this time with two German cup wins.
“RB Leipzig will always have a permanent place in my heart. I hope there will be a chance in the future to come back to Leipzig as a guest and play in front of the great fans again.”