Arsenal face losing Eddie Nketiah after convincing Folarin Balogun to sign a new deal at the Emirates.
The young forward has struggled for opportunities under Mikel Arteta and will see his contract expire in 2022.
The Gunners may therefore be forced into Nketiah's sale and West Ham are growing increasingly confident they can secure his signature, reports the Standard.
David Moyes lost Sebastien Haller in January and was unable to recruit a replacement at the time so is still in the market for an attacker.
Nketiah is highly thought of in north London but the majority of his 15 Premier League outings have come from the bench.
The 21-year-old endured a frustrating loan spell at Leeds last season and has been unable to enjoy consistent minutes during his career.
And with Balogun signing a new deal to compete with Pierre-Emerick Aubameyang and Alexandre Lacazette chances may be even more scarce for Nketiah.
The striker confessed last month that he has struggled with his lack of minutes.
He said: "It's been a difficult month or so for myself. I have worked hard and stayed dedicated and that has added to the frustration.
"It is a part of football but one that you don't want to be involved in. I believe in my ability so obviously I think I am capable of playing and helping the team.
"It is frustrating not playing but you have to channel that frustration in a good way, use your time wisely to work hard and prepare for when that opportunity arises."
Nketiah has scored 12 times for the Gunners with four of those coming in the league.
His only league goal this term came in the 2-1 win over West Ham back in September.
