The 22-year-old attacking midfielder sealed a move to Monaco in 2015, and has impressed for the Ligue 1 club this season after returning from a loan spell at Lille.
Lopes has racked up 11 goals in 39 appearances so far this campaign, establishing himself as a first-team regular for Leonardo Jardim's side.
The skilful prospect expressed his admiration for Portuguese compatriot and Manchester City winger Bernardo Silva.
"I'm happy for Bernardo, he's a friend and seeing what he's been doing in recent games with Manchester City is a very good thing," Lopes is quoted as saying by the Manchester Evening News.
"I'm very happy for him and I hope he'll continue to do beautiful things there. A return to City? Sure I would like to go back, but I am focused on Monaco. I'm fine here."
Lopes, while never featuring in the Premier League for City, did make a substitute appearance in the League Cup semi-final second leg against West Ham United in 2014.