Flamengo's director of football Paulo Pelaipe admitted they are waiting to hear back from the Premier League side if they will sanction the deal.
"The negotiation is well under way, but we have the transfer window problem as it's about to close," Pelaipe told UOL. "We are waiting for a signal from Arsenal.
"I don't want to talk about optimism or pessimism, as I don't want to make the fans create expectations.
"But if Arsenal accepted to talk with us and listen to offers, I think we won't have problems, let's wait."