Monaco vice president Vadim Vasilyev has told Arsenal that midfielder Thomas Lemar is not for sale.
The Gunners were chasing the France international but the Ligue 1 champions have outright rejected speculation he could leave before the end of the summer transfer window.
"I will address speculation relating to the case of Thomas Lemar. He is staying with us," he said. "He is an immense talent and is essential for the team.
"We have kept all of the key players that we intended to keep."
Arsenal launched a €35 million move for Lemar in June, though Monaco rebuffed their offer for the midfielder, who scored 14 times for the principality club last season, creating 17 more.
Vasilyev also addressed speculation regarding the future of Fabinho, who had been linked with Manchester United earlier in the transfer window.
"Fabinho stays, he is an essential player in the midfield,” he said.
Monaco have sold more than €165m of talent already this summer, including Bernardo Silva and Benjamin Mendy to Manchester City and Tiemoue Bakayoko to Chelsea while City are preparing a world-record bid for Kylian Mbappe.
Their transfer surplus stands at more than €100m.