Uncertainty about the world’s major economies is turning large Australian companies away from big spending.

Just one in 10 chief financial officers are willing to aggressively ramp up investments in 2015, compared with 30 per cent a year earlier, a survey by American Express found.

An aggressive rise in investment is classified as an annual increase of more than 10 per cent.

Falling commodity prices, a slowdown in China and financial uncertainty in Europe are dampening risk appetite among miners and professional services firms, American Express’ Australian vice president of global corporate payments Christine Wakefield said.

“CFOs, what they’re really trying to do is protect and preserve their profitability,” she said.

“They are wanting to be sure that when they place their bet on an investment, they know there’s a high probability of a return.”

But 60 per cent of CFOs predict improvement in the Australian economy in 2015, as a weaker Australian dollar helps exporters and interest rates remain low.

“Business confidence is not as high as it has been but … the low Australian dollar is making exports and products very attractive,” Wakefield said.

More than 30 financial directors of Australian firms with an annual revenue of more than $500 million took part in the study.

They were interviewed or polled online in November and December, before the Australian dollar dived from 85 US cents to recent levels below 76 US cents.