The Bundesliga club, who beat Schalke 3-1 on Saturday with Keita on the scoresheet, made the announcement via an official statement on Sunday afternoon.
It read: ‘Naby Keita will remain an RB Leipzig player until 30th June 2018. We wish to put the speculation about a January move to Liverpool to bed.’
The club's sports director Ralf Rangnick said: "We won't allow Liverpool to sign him early, even though they have shown renewed interest to bring him in during this transfer window."
The Reds agreed a deal for Keita last August - before a £48million buyout clause kicked in - which would see the 22-year-old remain with the Bundesliga club for the 2017-18 campaign before moving to Anfield this summer.
But, following the £146m sale of Philippe Coutinho to Barcelona, Jurgen Klopp's side had reportedly been hopeful of securing the Guinea international this month instead, with an additional bonus fee for RB Leipzig.