MSPs have expressed concerns about the impact of plans by BBC Scotland to shed nearly 200 jobs as part of a shake-up of the corporation's operations.
Ken MacQuarrie said the job cuts would not affect quality
BBC Scotland controller Ken MacQuarrie told the Enterprise and Culture Committee last month that cuts would free millions for re-investment.
But the committee's report said it was not convinced that BBC Scotland would be able to maintain programme quality.
It also urged "meaningful negotiations" on reforms between the BBC and unions.
Trade union members staged a one-day strike on 23 May over the BBC-wide plans to save £355m a year, which includes almost 4,000 job cuts across the UK.
Mr MacQuarrie believes an extra £10m could be re-invested annually in Scotland from 2008 if proposed reforms are completed.
But in its report published on Tueday, the committee said: "From the evidence it heard, the committee is not convinced that BBC Scotland can guarantee that both technical and programme quality can be maintained and indeed increased following any of the changes proposed."
The MSPs said they acknowledged the need for the BBC to respond to future challenges posed by digital switchover and by the need to offer value for money in terms of its operations.
They said: "It is not appropriate for the committee to make any comment on detail of the level of efficiency savings being proposed, the process of reinvestment or the nature of which posts are to be cut.
"These are operational matters for BBC Scotland. Nevertheless, the committee has major concerns at the current state of play."
The MSPs also said plans to increase the volume of the BBC's non-news output provided by independent producers would not necessarily benefit Scotland's creative industries and could lead to "a loss of critical mass".
They stated: "Although a small number of independent companies based in Scotland could benefit from what is being proposed, the committee considers that there is no guarantee that the flow of money and resources will remain within Scotland and this could be to the longer term detriment of Scotland's creative industries."
Reacting to the report, Stephen Low, National Union of Journalists representative for BBC Scotland staff in Glasgow and Edinburgh, said: "The committee are absolutely right to identify Ken MacQuarrie's plans as a threat to the quality of BBC programmes and services.
"We have always argued that the cuts and privatisations that are proposed couldn't stand up to outside scrutiny and this has proven to be the case."
However a spokesman for BBC Scotland said: "As the committee acknowledge, we believe that we have to offer the best value for money to our licence-payers as we move towards the digital switchover.
"We have always recognised that our proposals present difficult challenges and we do not underestimate them in any way.
"We will listen and address concerns but we do believe we can introduce the changes outlined while still maintaining the quality of our output.
"The increased programme opportunities that would result from our proposals will benefit all programme-makers, in-house and independent, no matter where they are located in Scotland.
"We have to listen to our audiences tell us they they want from the BBC and our firm intention is to do just that, providing enhanced local coverage in addition to our existing national output for example, and also offer a wide range of high quality programmes in drama, entertainment, sport and factual."
The report was published as unions representing BBC journalists and technicians met to decide whether to accept a deal on the job losses or to make a new threat of strike action.
Thousands of BBC staff across the UK who walked out last week were due to resume industrial action for 48 hours from Tuesday but the stoppage was averted after 20 hours of talks between the corporation and union officials last week.
The BBC has offered a one-year moratorium on compulsory redundancies and the postponement of plans to outsource some jobs.