Antonio Rudiger was told by Chelsea to either sign a contract extension or sit out in the cold, the UK Mirror reports.
The 27-year-old attracted the attention of Tottenham Hotspur and West Ham after Frank Lampard told him he should leave.
Although Spurs want him on a permanent basis, the Hammers are offering Rudiger a season-long loan contract.
But, unless Rudiger signs a 12-month extension, it is known that neither change will happen.
On his present deal, the German defender has 18 months left.
Before their 2-0 loss to Liverpool two weeks ago, Lampard made it clear to Rudiger that he is not in his plans for the coming season anymore.