Angelo Ogbonna will be released by Watford at the end of his contract next month.
The Italy international defender signed a one-year deal with the Hornets last summer after he was allowed to leave West Ham United following nine seasons in east London.
Ogbonna, 36, made just eight appearances this season and was the biggest name to be released when the club announced its retained list.
The centre-back began his career at Torino and, after two seasons with Juventus, joined West Ham in 2015, making 249 appearances for the Hammers.