The Department of Agriculture, Fisheries and Forestry has confirmed Australia imports snow peas from Zimbabwe "on a regular basis", as well as cut flowers.

"Australia has imported cut flowers (mainly roses) and snow peas from Zimbabwe for at least 20 years," a department spokesman said.

The department admitted it does not know whether the items are produced by farms controlled by the President Robert Mugabe.

"The question is irrelevant to [the Australian Quarantine and Inspection Service's] responsibilities and authority," a spokeswoman said.

Many of the farms still operating in Zimbabwe since President Mugabe began his campaign to seize land from white farmers nine years ago are controlled by the dictator and members of his regime.

But the Agriculture Department said it had no mechanisms to ensure imported goods were not profiting the regime.

"The question is irrelevant to AQIS's responsibilities and authority," the spokeswoman repeated.

"AQIS is a border agency charged with managing pest and disease risks to Australia."

A spokeswoman for the Foreign Minister, Stephen Smith, said "imports from Zimbabwe are not covered" by sanctions that have been in place against the Mugabe regime since 2002.

"To date, Australia and other like-minded countries have taken the view that general trade sanctions against Zimbabwe, as opposed to financial sanctions targeting the regime and its close supporters, would do more harm than good," she said.

The spokeswoman also said "imports of cut flowers and fresh vegetables from Zimbabwe have been very small in recent years".

Cut flower imports totalled $33,000 in 2007-08 while fresh vegetable imports totalled $20,000-25,000 at most over the past two financial years.

Hyperinflation in Zimbabwe is so advanced that the country will introduce a $100 trillion note, state media said on Friday.

The new bill would have been worth about $450 at Thursday's exchange rate.