Southampton centre-back Virgil van Dijk will join Liverpool when the transfer window re-opens on 1 January in a world record £75m deal.
The Netherlands international had been expected to join the Reds last summer after he handed in a transfer request.
But a move fell through when Liverpool apologised for making an alleged illegal approach for the 26-year-old.
The fee is the most ever paid for a defender – Manchester City paid £52m to Monaco for Benjamin Mendy in July.
Van Dijk said in a statement he was “delighted and honoured” to sign for the Merseyside club and accepted he had had a “difficult last few months” at St Mary’s.
He was left out of Southampton’s squad for their 5-2 Premier League defeat by Tottenham on Tuesday, prompting speculation he was set to leave the club.
“Southampton have agreed a fee that will set a new world record for a defender,” the south coast club confirmed on Wednesday.
The player only signed a new six-year contract last year, having joined the Saints from Celtic for £13m in September 2015.
However, Liverpool’s interest in the summer prompted a transfer request from the player which saw him forced to train alone by manager Mauricio Pellegrino.