About 40,000 BT and Openreach workers quit in the nation’s first strike since 1987.
According to the Communications Workers Union (CWU), hundreds of phone lines have been set up across the UK.
It is the first of two strikes, with another being held on Monday, after union members refused a £1,500 pay rise.
It comes a day after BT revealed its first sales growth in five years, spurred by a price increase sold to customers earlier this year.
BT reported that its revenue rose 1% to £5.1 billion in the three months to the end of June.
The CWU said the striking workers came from a number of different departments.
“They run all the maintenance of UK broadband services, but they also do the monitoring of national infrastructure from the NHS to the Department of Defense to the mobile phone poles.”
CWU General Secretary Dave Ward said: “The BT Group is motivating our members.
“The announcement of profits of hundreds of millions of pounds on the eve of the first national strike since 1987 demonstrates arrogance and complete contempt for frontline workers.
‘Our members have kept the country connected during the pandemic’
“This dispute is right at the feet of Philip Jansen (BT’s chief executive). He represents everything that needs to change about big business in the UK.
“Our members have kept the country connected during the pandemic. They deserve the pay rise they deserve, and that’s what they’ll get.”
‘Balance of complex and competitive needs’
A spokesman for BT Group said: “Earlier this year, we had a thorough discussion with CWU that lasted for two months, trying to reach a salary agreement.
“When it became clear that we were not going to strike a deal, we decided to continue giving our team member and frontline colleagues the highest paid bonus in over 20 years, effective April 1st.
“We have confirmed to CWU that we will not be reopening the 2022 salary review, given the best possible award.
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“We’re balancing the complex and competitive needs of our stakeholders and include a one-time investment to upgrade the country’s mobile and broadband networks, which are vital to the economy.” The UK and the future of BT Group – including our people.
“While we respect the choice of our fellow CWU members to strike, we will work to minimize any disruption and keep our customers and the country connected. .
“We’ve tried and tested our coworker absence processes on a large scale to minimize any disruption for our customers, and these have been proven in time. epidemic.”