Chelsea were in advanced talks with the Black Eagles over the transfer of the Nigerian international according to BBC journalist Oluwashina Okeleji.
Okeleji told Turkish-football.com yesterday that negotiations had reached an advanced level.
“Besiktas are in advanced talks with Chelsea but nothing has been agreed with the player,” Okeleji said.
The Istanbul giants are expected to cover his €1.1 million salary over the course of next season.
Omeruo is already well settled in Istanbul having played for cross-city neighbours Kasimpasa and established himself as one of the most sought after defenders while at the club.
Besiktas will be the 22-year-old’s biggest test so far as he will be in a genuine title challenging side and play Champions League football for the first time.
The Black Eagles won the league title last season and go into the 2016-17 campaign as one of the bookmakers favourites.