Cape Town - Manchester City have reinforced their defensive department with the signing of Aymeric Laporte from Spanish club Athletic Bilbao, the club announced.
Bilbao posted a leaving message from Laporte on their Twitter feed on Monday, saying his €65 million release clause had been paid and reports said he was due to travel to Manchester.
It means Pep Guardiola's Premier League leaders are set to surpass the £55 million they paid for Belgium attacking midfielder Kevin de Bruyne - Laporte's transfer fee translates as £57 million.
The 23-year-old will also become the second most expensive defender in history behind Virgil Van Dijk, who cost Liverpool £75 million from Southampton earlier this month.
Laporte thanked Athletic's fans in his Twitter message but said he was taking on "a new challenge in my professional career".
The 23-year-old Frenchman is Guardiola's sixth signing of the 2017/18 season and has joined in a deal until 2023.
"I am very happy to be here," Laporte said. "City are a club with a lot of ambition and they are one of the best teams in Europe.
"I am looking forward to working under Pep Guardiola and trying to help the club to achieve success."
Txiki Begiristain, City's director of football, said: "We are delighted to have signed Aymeric. We have assessed defensive options and he is a player we have admired for a long time.
"With his quality and ability to play out from the back, we feel Aymeric will fit in perfectly with Pep Guardiola's playing style."
"I don't want this to be a goodbye but rather a see you soon," he said. "Here, I'm leaving a unique and different club and I'll never forget it."
His signing will mean Guardiola has spent more than €200 million simply on reinforcing his defence alongside the acquisitions of Benjamin Mendy (€52m), John Stones (€47.5m) and Kyle Walker (€45m).