Young voters were in the Prime Minister’s sights as he rolled into Ipswich yesterday as part of his nationwide campaign to keep Britain in the European Union.

He spent almost an hour telling an audience, which included many first-time voters, that Britain’s economy and security would be more secure if they voted to remain in the EU in the upcoming referendum in June.

Students from hosts University Campus Suffolk, plus from Suffolk New College, Suffolk One, Ipswich School, Copleston High School, Northgate High School and St Alban’s Catholic High School, probed the premier on issues ranging from the renegotiation to more lighthearted questions about Mayor of London Boris Johnson’s Conservative Party leadership ambitions.

“It is going to be the choice of many people in this room,” he said. “Put the 23rd [June] in your diary and make sure you vote. Whichever way you vote, this is going to be a huge decision for our country and one I very much hope you take part in,” he said.

Our poll of more than 1,200 people across East Anglia last month showed that almost a third were still undecided about how they would vote.

Research from historic elections also shows that younger voters are less likely to turn out to have their say.

Mr Cameron dismissed accusations of scaremongering after being asked by radiography student Carolyn Roberts about claims the “in” campaign had launched “Project Fear” to fight a negative battle over the poll, claiming he was only interested in “Project Fact”.

“This is not about raising concerns and worries which aren’t there – they are real concerns and worries based on fact,” he said

Mr Cameron pointed to the length of time it took Canada and Switzerland to negotiate free trade agreements with the EU.

He added major economies would negotiate deals with the EU first and the UK second.

He also said he had no intention of resigning should the poll go against him, adding: “I don’t want to cloud the issue.”

“This referendum is about one question, it’s not about any one politician’s future or one Government’s future,” he said.

The vote represented a choice between a “Greater Britain inside the EU” or a “leap in the dark” outside of it.

He added: “We don’t do this as some sort of project of national vanity, we do it because Britain benefits. Of course we’re a great country and a great power, but I would argue that our membership of the EU also helps us to be strong in the world and to get things done.”

A university staff member challenged Mr Cameron over whether EU membership fees could be better spent on education funding and student maintenance.

He said the university system was stronger inside a “strong and growing economy”.