If Britons choose to stay in the EU they could benefit from more than one million extra jobs by 2030, Tom Watson says today.

As Labour returns to one of the core campaign themes of jobs and growth, amid jitters over the polls, Watson says an In vote could lead to a raft of new posts in digital services, energy and tourism.

Watson will focus on the importance of EU trade and the role of 200,000 British companies which export to the EU each year without having to pay tariffs.

The Labour deputy leader and former trade union official will return to traditional party dividing lines by warning of the risk of a “Tory Brexit” which would harm the economy and put jobs and public services at risk.

“Labour is clear that the UK’s membership of the EU is good for jobs and good for British workers,” Watson is expected to say.

“We are united in campaigning for Britain to remain in Europe. That’s because Labour values are at the heart of this campaign.

“We believe in standing up for working people whose jobs and communities depend on trade with Europe. We believe in standing up for the rights of everyone to be treated fairly at work – and for the rights at work that are guaranteed by our membership of the European Union.

“And we believe in the positive role our membership of the EU can play in the future – the more than a million new jobs our economy has the potential to generate if we remain in the European Union, helping to provide opportunities for the next generation.”

Watson’s intervention comes as part of a Labour “fightback” amid fears hoards of Labour voters are drifting towards Brexit because of worries over issues such as jobs, immigration and pay.

Yesterday Watson, a former minister, tackled the issue of immigration head-on and called for the EU to reconsider its rules on the free movement of labour to reflect public concern.