The review follows a series of public disputes between trustees of the Notting Hill Carnival Trust, that have led to a management reshuffle.
Carnival Trust CEO Claire Holder, who had organised the event for the past 13 years, was suspended in March, and former Trust vice-chairman Ansel Wong has taken over in the interim.
Wong was unavailable for comment as PRWeek went to press, but is understood to be leading the review of Carnival agency needs.
Incumbent Harwood & Co, which has handled PR for the Carnival for the past seven years, claims it is still contracted to handle the business.
Harwood founder and MD Stephanie Harwood said: 'We've not been told what our contract holds for the future.'
Last year saw 600 specially-trained stewards on duty in addition to the 10,000 police officers present, in a bid to prevent the violent crime that has marred the event in recent years.