The Spaniard has been on both clubs’ radars for the past few years, with his first-team struggles having had the pair on almost constant alert.
However, a new contract appeared to have all but ended their hopes of landing the right-back last year, with his new deal running until 2018 with a release clause of £18m.
Yet, even in light of more minutes on the pitch this season, he is once again eyeing the exit door at the Nou Camp, and l’OM coach Marcelo Bielsa has asked his side’s bosses to secure the 23-year-old.
Although he has a release clause, Barca are likely to sell for a lower fee if Montoya pushes for a move, which has further alerted the Ligue 1 high flyers.
Guaranteed action may tempt the Spain former U-21 star to the Stade Velodrome.