The showrunner said that John Hurt's version of the Time Lord does not alter the numbering of other incarnations.
> Doctor Who 50th: Digital Spy's 'The Day of the Doctor' review
Speaking at the Doctor Who 50th Celebration at London's ExCel, Moffat said: "He has no more ever called himself the 11th Doctor than he would call himself Matt Smith. The Doctor doesn't know off the top of his head [what number he is].
"If you worry about such things, and I do, then I specifically said John Hurt's Doctor doesn't use the title. [Matt Smith's Doctor] is in his 12th body but he's the 11th Doctor, however there is no such character as the 11th Doctor - he's just The Doctor, that's what he calls himself.
"The numbering doesn't matter, except for those lists that you and I have been making for many years. So I've given you the option of not counting John Hurt numerically - he's the War Doctor."
Moffat also responded to questions about The Doctor's regeneration limit, which was introduced in Tom Baker story 'The Deadly Assassin'.
"Paul McGann turns into John Hurt so they're not the same incarnation. He used up another regeneration and I expect he'll be in trouble shortly - you can't break rules laid down in 'The Deadly Assassin'," he teased.
Doctor Who's 50th anniversary special 'The Day of the Doctor' attracted 10.2 million viewers on BBC One last night (November 23), according to overnight figures.
Directly after 'The Day of The Doctor', viewers were treated to a trailer for the upcoming Doctor Who Christmas special.
Watch the promo for the festive instalment below: