Opposition Leader Malcolm Turnbull says Treasurer Wayne Swan ignored the elephant in the room, during his budget speech on Tuesday night.
"The deficit was so horrible that the treasurer couldn't even bring himself to mention it in his speech,'' Mr Turnbull told Fairfax Radio Network.
"This is the first time in history a treasurer has given a budget night speech and has not mentioned, has not had the guts to say, what the result of the budget is.
"He wasn't prepared to say that it was $58 billion in deficit, he wasn't prepared to say that the debt by 2012 would be $188 billion.''
Mr Turnbull played down suggestions that there was confusion in opposition ranks over what budget deficit a coalition government would have delivered.
Shadow treasurer Joe Hockey said on the Seven Network that a coalition government would have delivered a deficit $25 billion lower than the government's $58 billion figure, but Mr Turnbull said on another radio station that it was impossible to provide a figure.
Mr Turnbull later clarified the coalition's position.
"If we had been elected in November 2007, the deficit would be dramatically lower and the debt forecast for 2012 would be dramatically lower,'' he said.
"There's a whole lot of things we would have done differently. It's not just a question of spending less on the stimulus.
"If we had been elected, we wouldn't have done what Swan and Rudd did and talked up inflation. We wouldn't have egged the Reserve Bank on to put up interest rates last year, which obviously damaged business and put people out of work, reduced government revenues.
"We wouldn't have had an unlimited bank deposit guarantee, which flattened every part of the finance sector outside of the banks.''
Mr Turnbull described the budget's growth predictions as optimistic.
"Miracles do happen but not that often,'' he said.
"When people say 4.5 per cent (in 2011/12 and 20012/13) sounds a bit optimistic he (Prime Minister Kevin Rudd) then bridles and says you're attacking the integrity of the treasury.
"No one's attacking the integrity of the treasury ... what we're saying is, as reasonable people, that a dramatic and sustained turnaround at that level seems, given the history and experience, highly unlikely.''