A potential strike by BT workers over pay could result in faults on telephone and broadband lines remaining unfixed.
The Communication Workers Union (CWU), which is calling for the walk-out, is today distributing ballot papers to BT staff for them to vote over the strike.
The union says BT has double standards regarding pay, after staff were offered a two percent pay rise, with a £250 bonus and the potential for another £250.
However, Ian Livingstone, CEO of the company that made more than £1bn in profits last year, receieved a £850,000 pay rise, plus a bonus of £1.2m.
"We are seeking an affordable and reasonable pay rise for our members in BT who have contributed heavily to the success of the company during a difficult couple of years," Andy Kerr, deputy general secretary of the CWU, said.
"We are amazed at the aggressive attitude of BT bosses in the face of blatant double standards. The company's claim that a five percent pay rise for staff would lead to cutting back and making redundancies is an unbelievable fat-cat excuse - it would cost 3.6 per cent of available cash flow, hardly breaking the bank."
BT said it was "disappointed" the ballot for strike action was going ahead.
"BT has improved its offer several times but the union have not moved once from their opening claim," the company told Sky News.
"Their insistence on five percent this year alone, at a time when they're accepting around two percent from other companies, is puzzling and at odds with pay deals throughout the public and private sector."
A CWU spokesperson told CIO sister title PC Pro said the union couldn't give details of how long any strike may be or how many people would be involved, "but we think it would lead to widespread disruption in some areas".
"The biggest impact could be in fixing faults on exchanges or broadband lines - which would be on hold for the duration of a strike - and things that are scheduled to happen, such as laying new fibre or upgrading exchanges, wouldn't happen."
If the strike goes ahead, it will be the biggest walk-out by staff of the telecommunication company in 23 years.