The UK's long-term prospects could be "brighter" outside the EU, a business leader has said.
John Longworth, head of the British Chambers of Commerce, described the EU referendum as a choice between the "devil and the deep blue sea".
He told its annual conference that voters faced "undoubtedly a tough choice".
One option was staying in an "essentially unreformed EU", with the other being the uncertainty of leaving.
"The dynamism and resilience of the City of London and the UK business sector suggests to me that, in the long run, we have the capacity and capability to create a bright, if not brighter, economic future outside of the EU - just as we would have done had we had the opportunity to stay in a truly reformed Europe," Mr Longworth said.
He told the conference in London that his observation was based on key economic reports on the merits of staying in the EU and of leaving.
The BCC has said it was not aligned to either camp in the debate because its membership was split on the issue.
BCC members will be surveyed so their views could inform the debate ahead of the vote in June, he added.
Analysis: Kamal Ahmed, economics editor
It may be anecdotal, but businesses I have spoken to this morning suggest the leave EU campaign has had a reasonable start.
One theme is emerging from today's British Chambers of Commerce annual conference.
Yes, many businesses support remaining in the European Union, but many also say the "leave" campaign has had a good start.
And opposition to Brexit might be softening.
Mr Longworth also told delegates: "Decision making in business suffers from the pressures of the short-term and is naturally focused on the interests of the particular business concerned.
"If I were to ask the business community one thing in this referendum, it would be to look to the long-term and the wider interests of the society in which you operate, and make your choice based not on the next financial year, but on what you want for your children and grandchildren."
Sajid Javid, the Business Secretary, also addressed the conference and said it had been a "very difficult " decision to oppose Brexit.
"I have no time for closer political union and in many ways I am a Eurosceptic. I am still a Brussels basher and will remain so. I wish there was more in the deal," he told delegates.
"I accept that all businesses prefer a degree of certainty over uncertainty. I am not suggesting everything is certain by remaining but there is a lot more uncertainty on the other side. Uncertainty is the enemy of jobs and growth."
In an afternoon Q&A session, Chancellor George Osborne and German finance minister Wolfgang Schaeuble, argued the case for the UK remaining in the EU.
Asked what his reaction would be if the UK did vote to leave the EU, he said: "We would cry. But I hope we will not."
Asked about BMW writing to its 8,000 UK staff to highlight what it regarded as the risks of a vote to leave the EU, Mr Schaeuble replied: "If the management of a company ... is asked by employees 'what is your judgement?' - it is right to say what is best in the interest of the company."
The German car maker highlighted the "significant benefit" the company derived from the free movement of workers within the EU in the email.
Mr Osborne was asked about issue of red tape facing small and medium-sized businesses. He said many of the rules and regulations companies were unhappy about were from UK legislation rather than European law.