Valencia had a frustrating season with the West Ham last season after struggling with a persistent ankle injury and then finding first-team opportunities limited on his return.
The £12million signing from Pachuca in 2014 could plunge even further down the pecking order if Slaven Bilic manages to sign another forward this summer, with Jonathan Calleri expected to arrive and the club making moves for Mario Gomez, Wissam Ben Yedder and Carlos Bacca.
Valencia was strongly linked with a move to West Bromwich Albion back in May, offering him a wage packet of around £25,000 per week.