Industry insiders this week confirmed internet rumours that Saunders is to leave Nintendo at the end of April to take up the position.
Apple has also reportedly enticed Nick Grange, head of PR at computer gaming firm Activision, to join the firm at the same time.
It is understood that Grange will lead PR for the firm's hardware, including the iPod and iPad.
Saunders has worked at Nintendo for seven years, where he helped launch the Wii and DS. The appointment was due to be officially announced as PRWeek went to press, along with news of Saunders' replacement.
Grange's CV includes spells at Electronic Arts, Microsoft and Activision. It is not known whether a replacement has been appointed.
Saunders and Grange both declined to respond to PRWeek's enquiries.
Mark Pinsent, MD of Shine, said: 'It is unusual for Apple to make these high-profile appointments from within the industry - it hasn't done it for a while.
'Apple is seen as a very cool company, because it controls its marketing message very carefully. But there isn't a huge amount of leeway for in-house people or agencies when it comes to Apple comms, as it is largely done from the States.'
Apple declined to comment.