Optus has led opposition among telecommunications rivals to Telstra's plan to restructure and buy the national broadband network, saying it would be a terrible outcome for taxpayers, competition and consumers.

At its annual investor day last Thursday, Telstra unveiled its most significant corporate restructure since privatisation, creating three separate legal entities that could be spun off in the future. Chief executive Andy Penn said one of the groups, called InfraCo Fixed, could feasibly be a future acquirer of the government-owned NBN.