THE referendum on Britain’s membership of the EU will be an “era-defining moment” for workers’ rights in Britain, Jeremy Corbyn will say today.

The Labour leader, who has previously been a fierce critic of EU austerity policies, is planning to highlight new research by the party revealing how many workers benefit from EU employment law.

It shows that 26 million people are entitled to paid holidays through the working time directive, while over 10 million have benefited from rights for part-time, agency and temporary workers and 340,000 women a year benefit from maternity leave.

Mr Corbyn will warn that neither David Cameron or Boris Johnson can be trusted to retain those rights in the event of a Leave vote on June 23.

“A vote to Leave means a Conservative government would then be in charge of negotiating Britain’s exit,” he will say in a speech at London’s Institute of Engineering Technology.

“Everything they have done as a government so far means we could not rely on them to protect the workplace rights that millions rely on.

“A Tory Brexit negotiation would be a disaster for the majority of people in Britain.”

The speech comes amid a push to shore-up support among left-wing voters for the Remain campaign.

The TUC also claimed yesterday that workers’ rights were on the ballot paper on June 23 and warned that wages could be £38 a week lower outside the EU.

But there has been a surge in support for the Leave campaign this week, with three polls predicting Britain will break with Brussels.

RMT general secretary Mick Cash made the left-wing case for leaving the EU yesterday on BBC Radio 4’s Today programme.

He said: “We believe in strong links with trade unions across all borders.

“But the EU has been pursuing austerity policies, privatisation, deregulation and social dumping on a massive scale.

?“And what we’ve seen is a race to the bottom for workers.

“The EU has overseen a situation where workers have had their wages cut and trade unions have been stopped from taking industrial action.”