Senegal striker Sadio Mane has joined Liverpool from Premier League rivals Southampton on a "long-term contract" for an undisclosed fee, the Anfield club announced Tuesday.
British media reports suggested Mane had signed a five-year contract in a deal worth some £30 million ($40 million, 36 million euros).
That would make Mane, who scored 25 goals in 75 appearances for the Saints, Liverpool`s third-most expensive signing behind fellow strikers Andy Carroll (£35 million) and Christian Benteke (£32.5 million).
"Today is a big day and I am very happy to sign for one of the biggest clubs in Europe," Mane told Liverpool`s website. "It`s a club that has won a lot of trophies and has a big history.
"Now I am looking forward to meeting all the staff and my team-mates and starting the season."
Southampton finished sixth in the Premier League last season, two places above Liverpool.
But in terms of history, supporter base and finance, five-time European champions Liverpool remain a significantly `bigger` club than the Saints.
Mane is the fourth player signed by Liverpool manager Jurgen Klopp in pre-season, with the striker following centre-back Joel Matip, midfielder Marko Grujic and goalkeeper Loris Karius to Merseyside.
There have been reports that Liverpool are prepared to help finance the Mane deal by selling Belgium forward Benteke, who failed to sparkle last term following his transfer from Aston Villa.
Mane -- who will bring Southampton a huge profit on the £10 million they paid Austrian side Salzburg in 2014 -- is the fifth Saints player to leave the south coast club for north-west side Liverpool in the past two seasons.
He will now find himself sharing a changing room at Anfield with fellow Southampton `old boys` Adam Lallana, Dejan Lovren and Nathaniel Clyne.
Rickie Lambert, another former Southampton player, was also at Liverpool but has since moved on.
Mane, who scored 11 goals last term, is the second star name to leave managerless Southampton in the past week after Kenyan midfielder Victor Wanyama joined Tottenham Hotspur for £11 million.
Southampton, who did dip into the transfer market on Saturday by buying winger Nathan Redmond for £10 million from relegated Norwich City, have been without a manager since Dutch boss Ronald Koeman left to take over at Liverpool`s city rivals Everton earlier this month.
Liverpool players who have not been involved in the European Championships are due to return for pre-season training on Saturday, with their first friendly the following Friday at nearby Tranmere.