Fletcher left Manchester United to join the Hammers on a four-year deal last summer.
The 21-year-old was a free agent when he joined the east London club.
West Ham have finally agreed a deal with Manchester United for Ashley Fletcher
But a compensation figure between West Ham and United couldn't be agreed.
And the discussion over Fletcher's fee looked to be heading to a tribunal.
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However, the Daily Mirror now claim West Ham have finally agreed a £1m deal for the forward.
Fletcher has only made two Premier League starts this season.
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But he has featured 11 times from the bench, and can expect more game time now a fee has been agreed.