DAVID CAMERON’S appeal for a national pay rise is a “sick joke,” union leader Mark Serwotka blasted yesterday as Britain’s labour movement united to demand a major legal shake-up to claw back working-class power.

After years of public-sector pay freezes and savage austerity, the Prime Minister told an audience of top bosses it was time they coughed up.

“Economic success can’t just be shown in the GDP figures or on the balance sheets of British businesses … but in people’s pay packets and bank accounts and lifestyles,” he said.

And the Old Etonian audaciously echoed a TUC slogan coined two years ago in a report by Civil Service union PCS which argued government policies would cut £7 billion a year from public servants’ salaries. “Put simply, it’s time Britain had a pay rise,” Mr Cameron smarmed.

The pompous PM’s posturing came as trade union leaders, politicians and lawyers demanded major changes to Britain’s suffocating anti-union legal framework.

In an exclusive supplement to today’s Morning Star, trade unionists including Mr Serwotka, Unite general secretary Len McCluskey and TUC leader Frances O’Grady call for the government to lift the shackles preventing working people from fighting back against entrenched corporate interests.

Labour policy chief Jon Cruddas says the link between national wealth and family budgets has been firmly severed.

“Labour will build an inclusive economy where everyone’s hard work is rewarded and we create real and enduring prosperity for the whole country,” he argues.

Speaking after Mr Cameron’s speech at the British Chambers of Commerce, Mr Serwotka said: “Our report two years ago aimed to generate a serious debate about the effects of low pay on the economy.

“The fact the Prime Minister has finally caught up with this three months before the election could be seen as flattery, but is more like a sick joke.”

In today’s supplement, produced in conjunction with the Institute of Employment Rights, Mr McCluskey writes: “The ideologically skewed approach to employment relations of successive governments is at the heart of our broken economy, when in reality there are plenty of examples of where trade unions work positively with industry for mutual benefit.”

And FBU general secretary Matt Wrack says the labour movement must “unambiguously call for the repeal of the anti-union laws.”

But CWU leader Billy Hayes said Labour’s proposal for year-long tax breaks for firms paying the living wage was too soft.

What “happens after 12 months when the firm pleads an inability to pay?” he asks.

“A different approach is needed. Employers should be put on notice. Labour needs to oversee the move from a minimum wage economy to a living wage economy.”

Contributors to today’s supplement will launch their campaign for workers’s rights at an Institute of Employment Rights conference today, held at Unison’s central London headquarters.