Unai Emery's Gunners have been very proactive in the transfer market so far, securing five first-team signings ahead of the new Premier League season, which starts on 10 August.
But Football London's Charles Watts, who acts as the website's Arsenal's correspondent, has said there is no room left in the transfer budget to sign Dembele and only a temporary transfer is possible.
However, Barcelona are reluctant for the 21-year-old to leave the La Liga club, as he is included in the Catalan club's plans for next season.
Watts told Arsenal fans in a Football London Q&A: "Dembele on his own would cost far more than whatever money comes in from potential sales.
"Mislintat would love Dembele, that would be his dream signing and he would slot perfectly in as well. But unless Barcelona decide to send him out on loan, it's not going to happen."
Dembele had a disappointing first season at the Camp Nou following his €105m move from Borussia Dortmund twelve months ago. He missed five months of the campaign due to a hamstring injury, which limited the Frenchman to only 23 appearances in all competitions.
However Barca manager Ernesto Valverde has said that Dembele is still a wanted man at Barcelona and has a role to play at the club next season.
Speaking in May, Valverde told reporters, "Dembele is a player with a lot of talent, great technique, can use both feet, he's quick, he's got that spark, he unbalances defences".
"We think he can help us. He's very young and he has a lot of time head of him still".
It was not a completely disappointing 2017/18 campaign for the 21-year-old, however, as he helped France win this summer's World Cup over in Russia, making four tournament appearances for Didier Deschamps' side.