The professional services firm Deloitte’s latest survey of chief financial officers representing quoted companies worth almost £700bn reveals optimism rising for the second quarter in a row as immediate threats such as a eurozone break-up recede.

The more upbeat mood comes despite a backdrop of rising inflation and the prospect of a fresh dip for the economy in the final three months of 2012 as the UK suffers an Olympic hangover.

Financial chiefs say the risk of a euro break-up has slipped to one in five, compared to one in three a year ago, while corporate credit is at its cheapest and most plentiful for five years. Only 4 per cent of finance directors and chief financial officers cited raising finance as a major worry for the business.

But the economy remains the overriding concern as companies focus on cash flow, cost savings and boosting margins rather than breakneck expansion in an uncertain climate. Deloitte’s chief economist, Ian Stewart, said: “The emerging picture is of businesses which are constrained by low growth and uncertainty rather than weakness in business models or access to capital. We’ve seen a long-term drift to greater defensiveness by corporates, not for want of capital but rather for scarcity of opportunity.

“Confidence has returned, but perceptions of economic and financial uncertainty remain high, and the greatest worries for CFOs are still the weakness of the euro area and UK economies.”

Firms are still ready to invest, but are picking their spots carefully amid concerns over demand. Mr Stewart said companies had not “closed the door to growth”, but added: “The difference now is that such opportunities are more selective. CFOs cannot rely on the upward escalator of steady growth to lift revenues.”