Senior consultants working on a contract for the Department of Health each cost the executive £2,000 per day, MLAs were told, on 16 May 2012.
Consultancy firm Ernst and Young has a £660,00 two-month contract with the department to assist in the drawing up of population plans as part of the reform of health and social care.
The department's permanent secretary, Andrew McCormick told the health committee the plans would provide a "road map" for the transformation of the health service.
Mr McCormick indicated that "further support" from consultants would be needed to implement the plans. This further spending would need to be sanctioned by the health minister.
John Compton, chief executive of the Health and Social Care Board, said rumours of a £900,000 contract were "completely erroneous".
Health committee chairwoman Sue Ramsey of Sinn Fein said she remained to be convinced of the need for the contract.
The DUP's Jim Wells referred to Mr Compton as "the master of spin", and observed that the department was paying the consultancy £44k per member of staff for a period of two months.
Mr Compton said the tender had been "at the lower end of cost".
He said it would not have been possible to have carried out the work internally within the department.
Conall McDevitt of the SDLP asked for details of the rates agreed for individual senior consultants.
Pamela McCreedy from the Health and Social Care Board explained that Ernst and Young was charging £2,000 per day for the work of consultants Dr Richard Lewis and Dame Catherine Elcoat over a 15 to 20 day period.
Mr McDevitt described the rate agreed with the consultancy as "unbelievably generous".
At the beginning of the meeting, MLAs were told there had been an increase of 751% in the number of patients waiting 12 hours or more for treatment in accident and emergency departments since 2007.
An assembly researcher told committee members that the greatest number of breaches of the 12-hour rule in the previous six months had been in the Ulster Hospital, Antrim Area Hospital, and the Royal Victoria Hospital in Belfast.