Former News of the World editor Hall's contract expired in April, but he has been asked to stand down because of the club's perilous financial position.
Hall confirmed that West Ham's new owners David Sullivan and David Gold had asked PHA Media to quit 'because of the club’s financial plight'.
Hall added: 'I hope that when things are on a better financial footing, there may be a chance to return in a professional capacity.'
Last month West Ham were taken over by ex-Birmingham City owners Sullivan and Gold, in a deal that valued their 50 per cent stake in the club at £105m. At the time of the takeover, it was reported that the club had debts of about £100m.
PRWeek reported last week that Hall had been hired by former England captain and Chelsea player John Terry to manage his PR in the wake of allegations his has cheated on his wife.