Finance experts have slammed Treasurer Scott Morrison's comments on debt.

In a speech to a banking and finance conference in Sydney, the Treasurer suggested he would accept additional debt for infrastructure, if recurrent spending was under control.

Mr Morrison says there are good and bad uses of public debt.

“Bad debt is debt used for current spending purposes, no different than in a household,” he said.

“Borrowing for this type of recurrent expenditure at the Commonwealth level is not sustainable and it is vital that we reduce our borrowing for day-to-day government spending.”

Investment expert Roger Montgomery left no illusion in his criticism.

“I think that is one of the most inane and stupid things I have ever heard,” he told the ABC.

Mr Montgomery said asset prices were rising precisely because of the debt used to buy it.

“The reality is that firstly, if house prices are elevated because of debt, there should be no comfort in the price of a house — it's elevated simply because of the debt,” he said.

“When interest rates start going up — and they will as soon as, in some cases February for some of the banks — investors are going to find they won't have a tenant, or they won't have a tenant and they'll have higher interest rates to pay, and that debt will come home to roost.”

Urbis economist Nicki Hutley said it “is a little bit of a shallow statement”.

Baillieu Holst private client stockbroker James Rosenberg said no one should assume housing will keep its value.

“I think what Scott Morrison is saying, is he's trying to be comforting, but really investors should take no comfort from it at all,” he said.