"We are the fifth or sixth largest economy in the world. We could exist on our own - peacefully and sensibly," Lord Bamford, the head of the construction equipment manufacturer JCB, told the BBC news, adding that leaving the European Union would allow the UK to "negotiate as our country rather than being one of 28 nations".
The UK's construction boom had helped offset weaker markets globally, JCB said.
The construction equipment market in both Brazil and China declined by 17% last year, with Russia down 27% and India by almost 15%, it reported.
The market for plant machinery in the UK, in contrast, jumped by 30%, while in the US it rose 13%. Overall JCB said sales totalled £2.5bn, down 6% on 2013.
The firm was "well placed" to capitalize on improving growth in developing countries, Bamford said.
"The need for infrastructure in much of the developing world remains acute and will eventually drive a resumption of growth," he added.
In the meantime, British Chambers of Commerce director general John Longworth said that 55% of his members would welcome a "reformed Europe".
"The 'reformed' part of it is quite important, and if you look at a lot of the economic reports... the in-out debate is more nuanced than a lot of people would have us believe," he told the BBC.
BCC was expecting to see how reform proposals would be shaped, and that it was down to UK politicians to explain to business what reforms they would be pursuing from Brussels.
While businesses were used to dealing with uncertainty, an in-out referendum should "take place as as soon as is practical", Mr Longworth said.
Prime Minister David Cameron has promised an in-out referendum on the UK's EU membership by the end of 2017.
