Executive producer Rod Fergusson added that the game is on track to be the most polished Gears title yet.
"I know fans are going to be disappointed with the new release date, but rest assured that this is a business decision between partners, and not a quality issue," he said.
"Gears 3 was on track to be the most polished Gears of War game ever when it released in April, and this additional time allows us to polish it that much more before it hits shelves next fall.
"Next week we have a major multiplayer press visit at Epic HQ, and I'm really looking forward to the fans getting to see and hear about Gears 3 Versus multiplayer for the first time. Lots more exciting news to come."
Earlier today Gears of War 3 was delayed by a minimum of five months.
Explaining the shock move, Microsoft said that it wants the game to be "the marquee title for the holiday season", adding that "Gears of War 3 promises to be the biggest entertainment launch of 2011."