"Sergio Ramos has informed Sevilla FC that he will not stay next season," the club said in a statement.
The player's contract was set to expire at the end of the campaign.
Antoine Griezmann struck a hat-trick in a 3-0 win over 10-man Celta Vigo to help Atletico Madrid climb provisionally second, in hot pursuit of their city rivals.
Sergio Ramos has not played against Real Madrid since 2005 but on Saturday, his Sevilla team welcome the Spanish league leaders to the Sanchez-Pizjuan for a reunion.
Al-Hilal have signed Morocco goalkeeper Yassine Bounou from Spanish side Sevilla on a three-year contract, the Saudi Pro League club said on Thursday.
His message was one of pride, which is what he has restored at Roma, a team which has one of Italy's largest, most passionate fan bases but has won little of note since being founded in 1927.
Sevilla beat AS Roma 4-1 on penalties on Wednesday to win the Europa League for a record-extending seventh time, handing Jose Mourinho his first defeat in six European finals.
Marcus Rashford will miss Manchester United's Europa League quarter-final first-leg clash with Sevilla after suffering a muscle injury that is likely to keep him out for "a few games", the club announced on Wednesday.
European soccer's governing body UEFA has opened an investigation after Sevilla goalkeeper Marko Dmitrovic was attacked by a fan on the pitch in Thursday's Europa League match at PSV Eindhoven, The Athletic sports website reported.
After retiring from playing in 1991 he went on to manage Rayo Vallecano, Racing Santander, Sevilla, Atletico Madrid, Real Zaragoza, Real Valladolid, Malaga and Granada 74.
Sevilla have reached an agreement with midfielder Isco to terminate his contract, the LaLiga club said on Wednesday.
Real Madrid head coach Carlo Ancelotti believes the current Real Madrid squad may be the best that he has ever coached.
A goalless draw against Sevilla on Wednesday was enough to send Bayern Munich into the Champions League last four with a 2-1 aggregate victory.
Manchester United suffer a shock exit in the Champions League last 16 with a 2-1 loss to Sevilla while Edin Dzeko strike gives Roma a 1-0 win over Shakhtar Donetsk to send them through on away goals on Tuesday.
Sergio Escudero's goal after just 24 seconds set Sevilla on their way to a 3-1 win over Atletico Madrid and a place in the Spanish Copa del Rey semi-finals.
Sevilla coach Eduardo Berizzo will have surgery on Tuesday after being diagnosed with prostate cancer last week.
A Jose Callejon goal help Napoli ease into the Champions League group stage, while Sevilla also went through and Celtic suffer a scare in Kazakhstan before winning their play-off tie.
Atletico Madrid says they had signed Spanish international Victor Machin Perez, know as 'Vitolo', from Sevilla but immediately loaned him to Las Palmas to comply with a FIFA recruitment ban.
Leicester City say their signing of Vicente Iborra from Sevilla would be a four-year deal and they have agreed terms, with the fee reported to be in the region of 12 million euros (10.5 million pounds).
