The departing midfielder is part of a straight swap with Gunners forward Alexis Sanchez, says The Sun.
Mkhitaryan was seen with a beaming smile as his move to Arsene Wenger's Gunners looks set to be made official within the next 48 hours.
The Armenian winger has agreed a move to the Emirates, with Sanchez going the other way.
The deal is said to be a straight swap with no money involved – and all paperwork is complete.
Mino Raiola e Mkhitaryan deixando um hotel no centro de Londres mais cedo. [Sky Sports News] pic.twitter.com/GlSoqjm4Qz— Brasil Gooners (@brasilgooners) January 20, 2018