Arsenal are reportedly struggling to reach a compromise with Flamengo over a deal for defender Pablo Mari.
Over the weekend, Mari made the trip to London with the view of finalising a switch to the Emirates Stadium in the coming days.
However, an unnamed Flamengo director has suggested that Arsenal wish to change the terms of the transfer, which has resulted in the centre-back returning to Brazil.
According to Sky Sports News, the two clubs remain in negotiations, although a successful resolution is said to be far from a certainty.
Arsenal allegedly wish to sign the 26-year-old on loan until the end of the season, while possessing the option to sign the Spaniard on a permanent basis during the summer.
With Mari having contributed to the club's victory in the Copa Libertadores and their run to the Club World Cup final, Flamengo appear to have no interest in the terms which have been put forward to them.