Without waiting for the results of key reviews, the federal government has formally given new instructions to the company building the national broadband network to use a variety of technologies, in order to save time and money.

Communications Minister Malcolm Turnbull and Finance Minister Mathias Cormann issued a new statement of expectations to the board of NBN Co on Tuesday, effectively cementing one of six options contained in the strategic review released in December.

Malcolm Turnbull has finally indicated his preference for a mixed-technology NBN to NBN Co, which is building it. Credit:Andy Zakeli

The review highlighted a multi-technology mix as the best option for building the network. That means it will use a combination of fibre to street cabinets and existing copper to connect premises, as well as all-fibre connections for greenfield estates, pay-TV cables where available, plus fixed-wireless and satellite connections where required.

The previous government had mandated the use of fibre all the way into 93 per cent of premises.