We know that Ubisoft has never officially announced that they will be working on a new Prince of Persia game but there were hints that they might be working on one.
Drew James, Ubisoft’s Reflections Engineer did hint that there might be more Prince of Persia in the future. He tweeted some images from the past Prince of Persia games and followed that up with the tagline “what’s next for Prince of Persia” leading many to believe that there might be more Prince of Persia in the near future.
Since then, the only news we’ve got about the Prince of Persia game was when Ubisoft announce that the Sand of Time will be offered for free back in June. The game was offered as part of Ubisoft 30th anniversary celebration. As nice as that was, we refuse to believe that that was what James was hinting when he posted that tweet.