The House of Lords is scheduled to debate the Minimum Service Levels Bill at its second reading this afternoon.
Trade unions from across the UK and Europe have condemned the bill as an attack on workers’ right to strike.
Fire Brigades Union General Secretary Matt Wrack said:
“When firefighters and public service workers are put in the position of calling on the unelected House of Lords to defend their basic democratic rights, that is a sign of just how extreme and authoritarian this legislation is.
“We already have the most restrictive anti-trade union laws in the western world.
“Devolved governments and administrations, as well as trade unions from across Europe have condemned the bill as a draconian attack on UK workers.
“The Conservatives in Westminster are isolated in their attempt to keep wages down by crushing working people’s democratic rights.
“We will continue to resist this legislation every step of the way.”