An assembly committee has been told that the Executive would have £4bn less to spend following George Osborne's comprehensive spending review.
The Finance Committee was meeting to discuss issues including the spending review and industrial derating, on 3 November 2010.
Department of Finance and Personnel official Michael Brennan outlined the effects of the Westminster spending review on the Executive's finances.
He said that in the round the Executive would have £4bn less to spend over the next four years.
The UUP's David McNarry asked Mr Brennan whether he was confident that a budget could be agreed by Christmas. He replied that it depended on agreement in the Executive.
Mr McNarry said it was already November and there were signs of a drama emerging.
Sinn Fein's Mitchel McLaughlin asked about the timetable for agreeing a draft budget.
Mr Brennan said the timetable aimed at the agreement of a draft budget by 15/16 November to be presented to the assembly the next day.
Professor David Heald of the University of Aberdeen was next to give evidence on the spending review.
He said the review was much less bad than it might have been.
The professor said that although people criticised the Barnett formula, it was the formula that was protecting the devolved administrations.
These were "not the system-destroying cuts people have been talking about", he added.
Local representatives from the Confederation of British Industry gave evidence on delivering public services in a time of austerity.
The CBI's Terence Brannigan outlined the organisation's recently published report 'Time for Action'.
He said the report aimed to ensure that every pound spent on public services was a pound well spent.
The CBI suggestions were challenged by independent MLA Dawn Purvis.
She said that the proposals involving the privatisation and franchising of public services were about business making money by whilst more dependent on public finance.
The session concluded with an evidence session on industrial derating with DFP officials.