The Frenchman was a key part of Sunday's 5-1 win over Tottenham, but has refused to comment on whether he will be at the club next season.
Despite a surprising and impressive 5-1 hammering of Tottenham on the final day, the Magpies were condemned to their second relegation in seven years following Sunderland's 3-0 win over Everton on Wednesday night.
The Frenchman was nevertheless a key part in Sunday's win, which denied Spurs the chance to finish above bitter rivals Arsenal for the first time since 1995.
But the 26-year-old still found it difficult to hide his disappointment at seeing the club fall out of the top flight, admitting he is unsure as to whether he will still be at St James' Park next season.
According to the club's official Twitter feed, Sissoko said: "It's difficult to answer [whether I will stay] but I know this team and this club deserves to stay up. But we are in the Championship now so we need to do everything to try and come back for the next season because this club should normally be in the top 10 [of the Premier League].
"This season was hard for everyone but we need to carry on and work hard for the season after."
The dilemma of whether to stay on Tyneside is one shared by current boss Rafa Benitez, who was given a rapturous reception by Sunday's sell out home crowd, although the praise for the Spaniard has come as no surprise to Sissoko.
The midfielder continued: "He has a lot of experience as a coach. He has trained with Madrid, Napoli, Liverpool. He knows how to talk with the players, so he changed the tactics and mentality so I think that was good for everyone but maybe he came in a bit too late because we were already in the bottom.
"But I think he did his best and then we need to thank him for everything, and like I said we need to see what happens next season."