Final Fantasy XIII creators Yoshinori Kitase and Motomu Toriyama have stated that they'd be very interested in creating a direct sequel to Final Fantasy XIII, though they're waiting to see how well Final Fantasy XIII sells in the West.

"In the past three years we worked both on the world and on the various systems," says Kitase. "Creating these systems isn’t very glamorous and can frankly be a bit boring. If we could do a XIII-2, we could direct all our attention to the story and refine what we have already built."

"We do not know if there will be a XV. This depends a lot on the success of XIII. Also, it is difficult to pinpoint elements that are typical Final Fantasy. They are mostly invisible: part of the DNA of the game, that everyone recognizes as typical Final Fantasy. But ifthere is a XV, I hope the way we wrote our characters carries over. We strived to create believable people of flesh and blood. They are not robots. And they are not super heroes. I hope this humanity is something we will see again."

Source: SquareInsider