The 31-year-old arrived on Tyneside from Hull City in the summer 2016, giving up the chance to return to the Premier League with the Tigers despite scoring the only goal in their Championship play-off final win against Sheffield Wednesday.
Diame helped Newcastle to promotion at the end of the 2016-17 campaign, scoring thrice in 37 league games and has helped keep them up in the last two seasons, featuring in 60 Premier League games.