More than half of business leaders in the East would vote to remain in the European Union, according to a new report.

The figures, from the British Chambers of Commerce survey also revealed that the outcome of prime minister David Cameron's Brussels negotiations was unlikely to change how two-thirds of business chiefs would vote.

It came as the prime minister was holding talks in Brussels with key players from the European Parliament in an effort to keep his reform demands on track ahead of a crunch summit this week.

The survey of more than 100 people in the East of England showed 34pc would vote to leave the EU and 55pc would vote to stay.

Those representing larger firms were more likely to vote to remain than those in small and micro businesses.

Companies which export only to the EU expressed the strongest support for the remain campaign, while those exporting only outside the EU wanted to leave, according to the survey.

Norfolk Chamber chief executive Caroline Williams said: 'The findings suggest that for businesspeople, this is a question of in or out — not renegotiation.

'Business remains divided on Europe, and business leaders' views reflect the size of their firm and their export interests, rather than the current political debate.

'They are making rational economic choices based on their own interests.

'The findings are a wake-up call for both the remain and leave camps. Neither side can bank on a change to business opinion in the wake of any renegotiation settlement.'

A separate report found that 21 business federations across Europe are backing the prime minister's drive to make the EU more competitive.

The CBI and its counterparts in other countries including Germany and France published a joint letter backing reforms to boost jobs and prosperity.

Carolyn Fairbairn, CBI director general, said: 'There is a compelling shared benefit for firms to trade with no barriers inside a market of 500 million people and those crucial economic ties which connect us, creating jobs and investment, cannot be taken for granted.

'Improving the EU to make it more competitive in a global economy would be a real gain for firms of all sizes in the UK and across Europe.'

Are you campaigning to stay or leave the EU? Email sabah.meddings@archant.co.uk or call 01603 772879.