The Hammers bought the England Under-21 international from United for an initial fee of £650,000 and pay a further £250,000 every time he makes an appearance in their famous claret and blue shirts.

But a clause in his complicated contract allows Morrison to be sold if an offer of £18million and is made.

He can also go if the Upton Park team receive a one-off payment for £10m, according to the Daily Telegraph.

The 20-year-old midfielder has just 18 months left in his contract and if he does enter negotiations over a new deal in the next few weeks, he could be sold to fund transfer activity during the January window.