BT and Fujitsu have been invited to tender for the delivery contract in a strategy that aims to provide universal 2Mbps coverage, with next-generation speeds for at least 85 per cent of homes and businesses by 2015.
The project, known as Connecting Devon and Somerset, is led by the county councils in partnership with local authorities in Bath and North East Somerset, North Somerset, Plymouth and Torbay.
Almost £53 million has been secured to finance the broadband rollout, with £32 million coming from government agency Broadband Delivery UK, £10 million apiece from the county councils and additional funding from Bath and North East Somerset Council, which only joined the strategy in February.
The successful private sector bidder will also be expected to commit money to the project.
Will Mumford, cabinet member for economic regeneration and strategic planning for Devon County Council, said: "We will now be entering the procurement phase with both suppliers to secure the best deal possible for residents and businesses alike."
BT and Fujitsu have also this week been encouraged to bid for Suffolk's broadband delivery contract.
July 3, 2012