Liverpool sanctioned a deadline-day temporary move for Japanese star Minamino on Monday after Southampton allowed Shane Long to join promotion-chasing Championship side Bournemouth on loan.
Minamino has made 31 appearances and scored four goals for Premier League champions Liverpool since arriving from Austrian giants Salzburg in January last year.
The 26-year-old Japan international has scored one goal in nine Premier League matches this season, and four across all competitions.
"I am very pleased to welcome Takumi to our squad for the rest of this season," said Southampton manager Ralph Hasenhuttl.