Hammers owner David Sullivan told talkSPORT the day after they won the Europa Conference League that Rice had played his last game for the club.
The England midfielder will not come cheap, however, with West Ham valuing him at around £120million.
Arsenal have already seen a bid of £80m, plus £10m in add-ons, rejected and are expected to return with another offer.
There is late interest from Man City, but the Gunners remain the favourite landing spot for the 24-year-old.
Whatever the final fee will be, clubs know West Ham will be flush with extra cash they will splash out on to try and replace Rice and bolster other positions.
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talkSPORT.com takes a look at who the club could buy and how they could line up in the summer.
One player who is unlikely to sign is Edson Alvaraz from Ajax, with the midfielder set to replace Jude Bellingham at Borussia Dortmund on a £45m deal.
David Moyes is understood to want two midfielders in the summer and one of those could be Fulham's Joao Palhinha.
He impressed in Marco Silva's side, but the Guardian report he is likely to cost in the region of £50m.
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Southampton's James Ward-Prowse has also been a long-term West Ham target and another player unlikely to come cheap.
Like Fulham have with Palhinha, reports claim Saints are likely to demand around £50m.
Another relegated team is also in Moyes' sights with Harvey Barnes linked with the Hammers, although they will face competition from Tottenham and Aston Villa.
CBS journalist Ben Jacobs claims Lille striker Jonathan David, who scored 24 Ligue 1 goals last season, is a target to replace Gianluca Scamacca.
West Ham could help fund a move for David by cashing in on the striker who has struggled to settle at the London club.
Rice's sale will be a huge blow for the club and fans, but if they invest the money wisely then it could give them a huge boost on the pitch.
Moyes will hope he can build on the Europa Conference League success and get them challenging for those top six places once again.