Latu, who scored a hat-trick of tries in the Falcons’ final game of last season, skippered his country in the Pacific Nations Cup in June.
Returning with a knee injury which has required surgery, director of rugby Dean Richards revealed: “Nili suffered knee ligament damage playing in Tonga’s last Pacific Nations Cup game, and was operated on yesterday (Monday). His likely return to playing is five months from now.
“Obviously it is a disappointing to blow to lose a player of Nili’s quality for that length of time, but at the same time it is an opportunity for other guys.
“We have a lot of players coming through – Harrison Orr has joined us and made a very good first impression, but with David Tameilau not yet here from America there is no denying it has left us a little bit short in the back row.”
Newcastle’s players are a month into their pre-season training, the Premiership campaign kicking off at home to Sale Sharks on Friday September 2. Season ticket memberships are available from £208 for adults, £176 concessions, £70 under-16s and free for under-11s (two per paying adult). To book call 0871 226 6060.