'You need to come to an agreement among the public and private sector players as to what a sustainable debt level would be, and the parties all have to agree to share the burden of bringing the debt to that level.

Its proposed rules are to eliminate all borrowing so that the country can start paying off its debts, and to set a new sustainable debt target of about 40 per cent.

In a low-interest rate environment, it has become clear public investment can be funded by a higher level of sustainable debt than was previously believed to be the case, " he said.