This could be done by the Treasury as a form of expenditure or by the central bank itself. Both cases can therefore be seen as examples of fiscal policy with monetary financing.47 The Treasury would increase expenditure (or cut taxes) and the central bank would credit the Treasury account against a perpetual bond (a consol) with a zero coupon.
A debate ensued about whether this would be cheaper than normal bond financing when the central bank is doing QE and paying interest on the bank reserves. When consolidating the central bank account in the public sector, the maturity of public debt is changed from the perpetual bond into short term liabilities (reserves) the central bank has towards the banks.