ANZ chief economist Saul Eslake said the rapid decline of the domestic dollar will offset gains that might have filtered through to motorists because of lower oil prices.

The dollar came close yesterday to falling below US 70 cents for the first time since late 2004 — a fall of 29pc since July when it was more than US98c.

Meanwhile, West Texas Crude fell to below $US90 a barrel for the first time in eight months on the New York Mercantile Exchange.

"The effect of the movement in the exchange rate is to help people and hurt others," Mr Eslake said.

"The fall in the dollar means that less of the fall in international crude oil prices will be reflected at the pump than otherwise."

Farmers, exporters and the nation's tourism industry would benefit from the dollar's decline, Mr Eslake said.

"Farmers will love it, miners will appreciate it … It is good for manufacturers trying to sell stuff abroad or competing in the home market with imports that are less cheap now," he said.

People would be encouraged to holiday at home, he said.

"The fall in the dollar is a godsend for Australia's tourism industry in the sense that it makes Australia cheaper for foreign visitors and makes foreign trips more expensive for Australians and hence at the margin might encourage them to holiday at home."

AMP Capital Investors chief economist Shane Oliver said there was a risk that the falling dollar would push up the cost of imported goods.

"The bad news is it will put some upwards pressure on the prices for imported items like electronic goods, clothing and cars, although my feeling is that with the global economy and the Australian economy weakening it will be hard for companies to pass those increases on," he said.

CommSec chief equities economist Craig James agreed.

"In this sort of environment we are in at the moment, it would be a very brave retailer that would be forcing up the price of goods quite dramatically."

Mr James said companies that gained a high proportion of their earning from overseas tended to benefit from a lower Australian dollar.