BT's Openreach said it would connect fibre broadband into three million premises by the end of 2020, kicking off a drive to build the ultrafast network that Britain's homes and businesses have lacked.
Openreach, the country's national broadband infrastructure provider, said it would recruit 3,000 engineers in 2018 to ramp up its roll-out of fibre into premises, which can guarantee much faster speeds for users.
The Telegraph reported last week that BT's board was set to back committing more cash to Openreach for broadband roll-out.
The company, a wholly owned but independent unit of BT, said the pace and extent of the investment would be determined by the speed with which it can agree the terms of its return on the investment.
Openreach chief executive Clive Selley said the company was "getting on with the job of building an Ultrafast Britain".
"We are accelerating our plans to build fibre-to-the-premises to three million premises by 2020 which sets the course to reach 10 million by the mid-2020s with the right conditions," he said.
Openreach had previously focused on using a hybrid copper and fibre technology to bring faster broadband to British homes and businesses, an approach it has said is quicker and more cost effective.
But critics have said Britain has fallen behind in the provision of "gold standard" broadband connections needed to develop its digital economy.