Liverpool have signed Senegal forward Sadio Mane from Southampton for £34m.
The fee could rise to £36m, which would make him the Anfield club's most expensive signing, beating the £35m paid for striker Andy Carroll in 2011.
Mane scored 21 goals in 67 Premier League appearances for Saints after joining for £10m from Salzburg in 2014.
"Today is a big day and I am very happy to sign for one of the biggest clubs in Europe," he told the club's official website.
"It's a club that has won a lot of trophies and has a big history."
Liverpool manager Jurgen Klopp revealed he had been tracking Mane "since his impressive performances in the Olympics in 2012".
"Since I came here I have spoken to the staff a lot about him and have always felt he could be a very good signing for us," the 49-year-old German added.
Mane becomes the most expensive African player in history, with his transfer topping the £28m Manchester City paid Swansea City for Wilfried Bony in January 2015.
He is the fifth player to make the switch from St Mary's to Anfield since the summer of 2014 - following Adam Lallana, Rickie Lambert - now at West Brom - Dejan Lovren and Nathaniel Clyne.
Mane played out wide and centrally for Southampton, and will compete with the likes of Daniel Sturridge, Divock Origi, Danny Ings, Roberto Firmino and Christian Benteke for a place in the side.
However, Benteke - a £32.5m signing from Aston Villa last summer - has said he will consider leaving if Klopp continues to leave him out next season.
Southampton have already sold Victor Wanyama to Tottenham for £11m, and remain without a manager since Ronald Koeman departed for Everton.
Frenchman Claude Puel, 54, who led Nice to fourth in the French top flight last season, is the favourite for the vacant manager's position at St Mary's.
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