LABOR'S fresh food tax and the damage it will cause, by driving up the cost-of-living and making groceries more expensive, were subject of an investigation by a senate committee in April.

Leader of The Nationals David Littleproud said the fresh food tax, which is due to be implemented on July 1, is as an attack on families and farmers.

He said the biosecurity protection levy will force farmers to pay for the biosecurity risks of international importers.

“The outcome of the senate inquiry in Canberra is crucial because this new tax will impact almost every single Australian family and farmer,” Mr Littleproud said.

"It will hurt families at a time they can least afford it and farmers who are already under pressure.

“Farmers will be forced to pass on costs, meaning families will feel more pain at the grocery checkout.

"In what parallel universe would a government charge its own farmers to pay for the risks their competitors are creating?”

Mr Littleproud said every family and farmer deserved to feel angry that the fresh food tax had already been passed in the House of Representatives.

Ahead of the inquiry, Dandenong North chestnut farmer Luciano Cester has written to every Federal Senator, urging them not to support the tax.

“Primary producers like myself will likely attempt to compensate by scaling back production from the rise in cost associated with a new biosecurity tax,” Mr Cester said.

“If demand for goods remains the same or increases, this manufactured scarcity of production will contribute to a rise in prices for agricultural goods to consumers.

“The Australian economy and farmers should not be made to bear the additional financial burden of this new biosecurity tax.”