After several rumours and teases over the last weeks, Takashi Iizuka, the leader of Sonic Team, has officially confirmed that a new Sonic game is currently in development.
"We at Sonic Team "“ are developing a completely new game, as well as developing a full movie, actively done by Sony Pictures, and animation on Sonic Boom," said Iizuka. "We are also ready to improve sponsor ties. The most important thing is not the fact the series survived for 25 years, but how many games was developed. Our goal "“ add something new and overcome any potential hardships."
With SEGA holding a special Sonic 25th Anniversary party on the 22nd of July, where they teased that a special announcement will be made, it seems likely that the game will be revealed at the event.
Source: Nintendo Everything