British companies' appetite to borrow and issue debt is at the lowest level since the financial crisis, with demand for credit well below average levels and flagging, according to Deloitte's quarterly survey of chief financial officers.

Some 70% of the CFOs surveyed rated credit as "costly", reflecting a rise in Britain's base rate to 3.5%, and only 28% of them expected their company's demand for it to increase in the next 12 months.

In addition, 45% of the CFOs said new credit was hard to get, the survey found.

Deloitte's chief economist Ian Stewart said the most aggressive tightening of monetary policy in more than 30 years was reshaping corporate attitudes to debt.

"Not since the credit crunch have CFOs rated debt as being less attractive as a source of finance for their businesses than they do today," he said.

"When interest rates were at very low levels, debt finance easily eclipsed equity as a source of finance. CFOs now see them as being roughly on par."

Despite the challenging economic environment, the executives' perception of external risk, and in particular inflation, had eased since October's peak, the survey found.

On average the CFOs forecast inflation, which stood at 10.7% in November, would fall to 5.8% in a year's time and would be 3.3% in two years' time, it said.

Deloitte said it surveyed 78 CFOs, of whom 17 were from companies in the FTSE 100 and 32 were in the FTSE 250, between Dec. 6 and Dec. 16.

(Reporting by Paul Sandle; Editing by Alex Richardson)