The Liverpool defender hasn't played for Cameroon since 2015, but has rejected national coach Hugo Broos' attempts to convince him to return to the squad.
But Liverpool manager Jurgen Klopp will now be able to call upon the 25-year-old for crucial games in January, including crunch ties against Manchester United and Chelsea.
Matip is expected to return to the Liverpool team for Sunday's game against West Ham, after missing last weekend's defeat at Bournemouth with an ankle injury.
Source: DSG