West Ham manager David Moyes wants Besiktas defender Domagoj Vida next season according to Takvim.
Per the source, Moyes has made the Croatia international a transfer priority.
Vida has been added to the Hammers shortlist but a potential move could depend on whether the club remain in the Premier League next season.
READ: West Ham send scouts to watch 22-year-old Lille star Zeki Celik
Besiktas want to sell Vida in order to reduce their wage bill. The club are in a bad financial state and must sell players this summer.
The Black-Whites have, however, struggled to move Vida on due to his high wages.
Vida is the highest-paid player in the squad earning approximately €3.5m per-season.
The 30-year-old will still have another two-years remaining on his contract at the end of the season.
Vida has been a star name for Besiktas over the past few seasons and was part of the Croatia national team that reached the 2018 World Cup final.
The powerful defender has 79 international caps for Croatia and is expected to be first-choice centre-back at Euro 2020 this summer.