21-year-old Donnarumma is out of contract in June 2021 and Milan hope to renew his deal.
Chief executive Ivan Gazidis and Mino Raiola, Donnarumma’s agent, will have a meeting when the borders reopen in June.
With the uncertainty surrounding Donnarumma, Milan must look at potential replacements.
Rajkovic, 24, is arguably the best goalkeeper in Ligue 1 and has won 13 caps for Serbia.
He has played 27 of Reims’ 28 league games this season, conceding just 18 goals and boasting 12 clean sheets.
His performances have meant Reims having the best defensive record in the French league – even better than PSG.
After four seasons at Israeli club Maccabi Tel Aviv, Rajkovic joined Reims for €5m. Milan could expect to pay much more than that if they pursue him.
For now, everything depends on the future of Donnarumma with Milan awaiting confirmation on his plans.
If the young Italian decides to leave, Predrag Rajkovic may be the chosen one to replace him at the San Siro.