The 25-year-old, who has been capped 10 times by France, has agreed a six-year contract, which will begin on 1 July. 

'I am incredibly happy to be joining Chelsea,' said Nkunku. 'A big effort was made to bring me to the club and I am looking forward to meeting my new coach and teammates and showing the Chelsea supporters what I can do on the pitch. 

'Having played in Ligue 1 and the Bundesliga, I now want to play in the Premier League, one of the strongest leagues in the world. I am very excited for this challenge and will be proud to wear the Chelsea shirt.'

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. 

'He has demonstrated his ability at the highest level with RB Leipzig and France and we look forward to him joining up with his new teammates ahead of the new season.'

Nkunku is a graduate of the famed French national football academy at Clairefontaine and started his professional career at Paris Saint-Germain. He made 78 first-team appearances and was involved in three Ligue 1 title wins and two Coupe de France triumphs before departing for RB Leipzig in the summer of 2019. 

It is in Germany that Nkunku built his reputation as one of the finest forwards in European football. He scored 35 goals in all competitions during the 2021/22 campaign and was named Bundesliga Player of the Season and German PFA Player of the Season. The DFB-Pokal was also won. 

The versatile attacker struck a further 23 goals this season to help Leipzig secure a third-place finish in the Bundesliga and retain the DFB-Pokal. 

Welcome to Chelsea, Christopher!