West Ham co-owner David Sullivan says a deal has been agreed to sign Alex Song from Barcelona, if the midfielder can pass a medical.

The 27-year-old Cameroon international spent last season on loan with the Hammers and impressed sufficiently to earn a permanent move and a three-year contract, as long as the former Arsenal midfielder can prove his fitness.

Speaking to the KUMB (Knees Up Mother Brown) Podcast, Sullivan said: "We have a deal in place with Alex Song subject to a medical. If the medical is okay, we'll take him.

"He's a player we all admire and we just hope that the medical shows he's in a sufficient state for us to gamble.

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"He couldn't physically pass a medical tomorrow, but if the medics say it's just a technical thing and he's only a couple of weeks away you'd take that gamble and hope they're right.

"He's still got two years left on his Barcelona contract and you're signing a player on a three-year contract, so it's a huge commitment. He's a big earner, Alex.

"He's injured at the moment, which is something you've got to weight up. But we've got until September 1st to make a decision."

Song starred for West Ham in the first part of last season but his form faded like the team's.

Sullivan added: "On his pre-Christmas form he was possibly the best player we've ever signed. But after Christmas he was just another player.

"Maybe there's reasons for that and maybe we'll see the true Alex Song and maybe he'll make a huge contribution this year.

"We'd like another senior pro in that position."