The 29-year-old left the pitch on a stretcher during his national team's 2-2 draw against Slovakia in Dublin on Tuesday. Elliot will also miss the 2016 Euro in France in June-July, Newcastle announced on Wednesday, reports Efe.
Newcastle also miss the efforts of Dutch international goalkeeper Tim Krul, who sustained a knee ligament injury on international duty.
In the absence of the two regular goalkeepers, Karl Darlow, 25, will be playing the rest of the English Premier League (EPL) games, although he lacks required experience.
Darlow moved from Nottingham Forest last summer, but he played only two games with Newcastle, while the fourth choice Fred Woodman, 19, will be a substitute.
Newcastle are in 19th place in the EPL table, just three points ahead of last place, as the team got only one point during the last two matches since the arrival of Spanish head coach Rafa Benitez. (IANS)