The likes of Liverpool, Southampton, Celta Vigo, Napoli and Fiorentina have all been linked with a move for the highly-rated 20-year-old, who made just five Bundesliga starts during his debut campaign at Dortmund last term.
However, his agent Muzzi Ozcan has now confirmed that Inter have won the race for his signature, with the Turkey international expected to put pen to paper on a five-year deal next week.
"We have reached an agreement with Inter. The truth on the rumours linking him with Napoli is that the club simply wasn't interested," Ozcan told AreaNapoli.
Mor scored once in 19 appearances across all competitions for Dortmund last season.