There is also a “preliminary agreement” for the Armenian international to stay at the Stadio Olimpico for next season.
“I’m happy to stay here because I still have things that I haven’t achieved yet that I want to achieve,” said Mkhitaryan.
“I’m looking forward to it, I’m looking forward to finishing this restart of the season on a high note and then to be focused on what’s next.”
The 31-year-old former Manchester United player has scored six goals in 15 league appearances for Roma this term.
The capital club sit fifth in Serie A with 10 games remaining, but nine points adrift of Atalanta who occupy the fourth and final Champions League qualifying spot.
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