The club confirmed what has been expected for a while. The Frenchman joins on a seven-year deal for a fee of £75 million.

The London side will be paying £70 million, with a further possible £5 million in add-ons. It was their fourth and final bid for the centre-back as he finally joins Thomas Tuchel's brigade.

The previous offers were reported to be between £60 and £70 million, as the defender had not been showing up to training to force his move to the capital.

He was also not part of the squad at the weekend when the two sides met at Stamford Bridge where Chelsea won 2-1 despite being down to 10 men for much of the encounter.

On completing his signing, Fofana said to the Chelsea website: "The two last days have been really big days for me and I’m very happy. I trained this morning with the team and it’s a dream for me. I’m very excited to start playing games for the fans and the club.

"I’m here to win trophies – the Champions League, Premier League, FA Cup, Carabao Cup, everything. I came here to win and the club is built to win trophies so I’m here to continue that."

Chelsea chairman Todd Boehly added: "Wesley is a hugely promising defender who has already proven his quality in the Premier League at a young age.

"We are delighted we were able to bring one of Europe’s most exciting talents to Chelsea and further strengthen that area of our squad, both for this season and many more to come."

Fofana flew to USA to undergo his medical following the agreed fee on Saturday and will be in contention to play at the weekend. His new side lost 2-1 to Southampton on Tuesday night.