Barcelona are interested in signing Pierre-Emerick Aubameyang from Arsenal.
The La Liga club are willing to offer former Liverpool midfielder Philippe Coutinho in part exchange for the Arsenal captain.
Earlier on Monday, Barcelona president Joan Laporta revealed the club are £1.15bn in debt.
Aubameyang, 32, signed a new three-year deal with Arsenal last year until 2024.
The Gabon striker missed the Gunners' opening-day Premier League defeat at Brentford on Friday through illness, alongside Alexandre Lacazette.
Aubameyang, who joined Arsenal for a then club-record fee in the region of £60m in January 2018, scored 15 goals for the north London club last season as Mikel Arteta's side missed out on European qualification for the first time in 25 years.
Barcelona tried to sign England striker Tammy Abraham from Chelsea, report Sky in Italy.
Abraham, 23, completed a medical in Rome on Sunday ahead of completing a permanent move to the Serie A club for £34m.
Campbell questions Auba, Lacazette absences
Speaking to Sky Sports News, former Arsenal striker Kevin Campbell said: "Something is awry. Something isn't right.
"Right up until the [Brentford] game they [Aubameyang and Lacazette] were going to be in the starting line-up and then all of a sudden they are out. If they are ill let us know what the illness is.
"I just feel like there is some infighting going on at some stage. Arsenal don't need this because there is some serious work to be done [in on-field performances]."
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