The EU referendum is shaping up to be a battle between fears over the economic risks and immigration, according to new research.

Leading pollster John Curtice analysed surveys on attitudes to produce a more detailed picture of what factors are driving each side.

The work, carried out for the NatCen think-tank, found 73% of those who want to remain in the EU think Brexit would harm the economy, and 68% are convinced jobs would be lost.

By contrast leave supporters seem to put less stress on the economic case, with 59% believing we would be better off economically, and 32% suggesting it would make no difference.

Nearly two thirds of the Brexit backers insist immigration cannot be tackled while the country is inside the union.

And a huge 92% want to introduce an Australian-style points based system for accepting arrivals from the EU - a step that would be impossible under current freedom of movement rules.

Some 56% of those who want to stay say the UK would not be able to control immigration even if we did leave.

Professor Curtice warned that the sides could end up "talking past each other" as they ignore areas where their arguments are weaker.

"These findings pose a challenge for both sides of the referendum campaign," he said.

"Do they seek to persuade voters on those arguments where even their own supporters are currently less likely to be convinced?

"Or, do they seek to focus debate on the issue on which they are seemingly the stronger?

"The first option would perhaps help the public make a more informed decision.

"More likely, however, is the second, which could mean the two sides spend the campaign talking past each other and leave voters having to work out for themselves the merits of the arguments on the key issues."