West Ham midfielder Ravel Morrison has been fined STG7000 ($A10,400) by the Football Association for a homophobic Twitter post.

Morrison, who joined West Ham from Manchester United in the January transfer window, made the remark during an exchange with another user on the micro-blogging site.

The 19-year-old was also warned on Wednesday about his future conduct by the FA after admitting a charge under Rule E3 of the governing body’s disciplinary code.

This prohibits the use “of abusive and/or insulting words including a reference to a person’s sexual orientation”.

Morrison was widely regarded as one of the most talented youngsters ever to be unearthed by Manchester United, but was sold by the English champions to second-tier West Ham amid ongoing off-the-field problems.

Two days after winning the 2011 FA Youth Cup, Morrison was fined STG600 by a court for throwing his girlfriend’s mobile phone out of a window during an argument.

He also pleaded guilty to two counts of witness intimidation last year and has a police caution for assaulting his mother.