BT workers have voted overwhelmingly to strike in a dispute over pay, the Communication Workers Union (CWU) announced.
It is the latest development in a summer of industrial unrest which has seen a major strike on the rail network while tube workers and barristers have also walked out.
Members of the CWU at BT and Openreach overwhelmingly backed industrial action.
General secretary Dave Ward said BT was facing the first national strike since the company was privatised in the 1980s.
Mr Ward said it was the first time a group of call centre workers had voted for industrial action.
A vote by CWU members at EE failed by a few votes to reach the legal threshold.
Mr Ward said he expected BT to offer a “significantly improved” pay rise by next week or strike dates will be set.
He said his members had “kept this country connected during the pandemic” and said without them there would have been “no home-working revolution”.
He said: “This work, which was done under great difficulty and often came with tremendous personal sacrifice, delivered £1.3 billion profits for the company.
“Over £700 million was paid out to shareholders. The company’s CEO, Philip Jansen, handed himself a £3.5 million pay package – a 32% increase. Over £700 million was paid out to shareholders, and the chief financial officer was handed £2.2 million – a 25% increase.
“The reward for our members? The imposition of a below-inflation increase – the very same workers who delivered profits more like lottery numbers than actual wages.”
The union said it wanted a “substantial” pay rise, especially with the spiralling rate of inflation, arguing BT could afford it.
A BT Group spokesperson said: “BT Group awarded its highest pay rise for frontline colleagues in more than 20 years – an average 5% increase and up to 8% for those on the lowest salaries.
“At the same time, we’re in the middle of a once-in-a-generation investment programme to upgrade the country’s broadband and mobile networks.
“These investments are vital for the benefit of our millions of customers and for the UK economy. Above all, they are central to the success of this business – and its colleagues – now and in the future.
“Our job is to balance the competing demands of BT Group’s stakeholders and that requires careful management, especially in a challenging economic environment.
“The result of the CWU’s ballot is a disappointment but we will work to keep our customers and the country connected.”