No guarantees on NBN speeds, says chair Ziggy Switkowski THE chairman of the company building the National Broadband Network has distanced himself from government guarantees to provide minimum download speeds to Australian homes and businesses over the new-look NBN. Speaking before a Senate committee hearing today in Sydney, NBN Co chair Ziggy Switkowski said the company could not guarantee the minimum download speeds that the Abbott government had promised in the lead up to the September federal election.. I do not buy questions that demand us to guarantee anything. It's clear that after four years of NBN, guarantees have lost currency," Dr Switkowski said. In those election pledges, the now Communications Minister Malcolm Turnbull had said most homes would be able to access download speeds of at least 25Mbps. The 25 mbps speed is not either an average speed or an average peak connection speed. It is the minimum line speed that the network will be designed to deliver. In other words nobody will be in a position where they cannot access at least 25 mbps," Mr Turnbull said soon after the release of the Coalition's NBN policy in July. EXCLUSIVE: Vow to bring down NBN bill But Mr Turnbull last week formally dumped that signature election promise when he released the highly anticipated strategic review into the NBN. Instead, the Coalition has now pledged to deliver 91 per cent of homes with download speeds of 50Mbps broadband speeds by 2019 through a mix of fibre optic cabling, and the existing copper and cable networks. The strategic review, released last Thursday, predicted that the Coalition's NBN would need $41bn in funding - up $11.5bn on the $29.5bn the Coalition had estimated in April. It also found that, had Labor's all-fibre model continued, the project would have cost $73bn and earned a 2.5 per cent return - insufficient to treat it as an off-budget investment. The Coalition's model could earn a 5.3 per cent return.