Nintendo has issued an apology for "failing to include same-sex relationships in Tomodachi Life", its forthcoming life sim game.

Tomodachi Life has already been out for a while in Japan but is releasing worldwide to 3DS next month.

It will allow gamers to create Miis that will live out their lives, including dating and marrying, in their games.

However Nintendo has found itself on the defensive after gay advocacy group GLAAD slammed the gaming giant for supposedly patching gay and lesbian relationships out of the game. 

The controversy has been rumbling on for some time after a patch issued to the Japan market removed the possibility of Miis having same-sex relationships with each other.

The original Japanese release, Tomodachi Collection, allowed male characters to marry each other and raise children but it turned out this was because of a glitch and not actually intended by Nintendo.

Nintendo then responded to the glitch by issuing a patch to fix the "bug", removing the possibility of the male Miis forming same-sex relationships.

A backlash ensued not only in Japan but among Nintendo followers around the world and some Japanese players reportedly refused to install the patch in protest to the gaming manufacturer's presumed stance on gay relationships.

Nintendo then sought to explain that there really was no controversy at all but rather just a big misunderstanding.  In a statement to gaming blogger CandyCrushCopeland last month, Nintendo said male characters were never able to enter into same-sex relationships.  It had only looked that way because some Japanese gamers had dressed female characters in male clothes.

The statement then explained that the patch had been issued because dressing the female characters in male clothes resulted in a "critical bug" that "made it impossible for the player to continue the game".   

However GLAAD waded into the conversation and accused Nintendo of deliberately excluding gay relationships.

GLAAD spokesperson Wilson Cruz told VentureBeat: "In purposefully limiting players' relationship options, Nintendo is not only sending a hurtful message to many of its fans and consumers by excluding them, but also setting itself way behind the times.

"It's been over a decade since The Sims - the original 'whimsical and quirky' life simulator - allowed its users to marry any character they wanted, and many other mainstream and massively popular video games have followed their lead since.  Nintendo should do the same."

In response, Nintendo has now issued a statement in which it affirms its corporate goal is to create "fun and entertainment for everyone".

It apologises for "failing to include same-sex relationships" in the game but adds that it is not possible to change the current format.

Instead it promises to introduce gay relationships in any sequel to Tomodachi Life.

"We apologise for disappointing many people by failing to include same-sex relationships in Tomodachi Life," Nintendo said.

"Unfortunately, it is not possible for us to change this game's design, and such a significant development change can't be accomplished with a post-ship patch.

"At Nintendo, dedication has always meant going beyond the games to promote a sense of community, and to share a spirit of fun and joy. We are committed to advancing our long time company values of fun and entertainment for everyone.

"We pledge that if we create a next instalment in the Tomodachi series, we will strive to design a game-play experience from the ground up that is more inclusive, and better represents all players."