Ravel Morrison has finalised his move from Manchester United to Championship side West Ham United.

The 18-year-old made the decision to leave the Premier League champions because of a lack of first-team opportunities.

"Ravel is a talented lad and if he really wants to be a player then we will help him as much as we can along the way," said West Ham manager Sam Allardyce.

"Perhaps a change of environment will be beneficial to him and help him make that step up to first-team football quicker than perhaps would have been the case at Manchester United."

Morrison has signed a three-and-a-half-year deal at Upton Park.