Agriculture Minister David Littleproud said in a statement that detections of the pest at international borders were increasing worldwide, and an outbreak in Australia could cost more than $15.5 billion over 20 years.

He said the $14.5 million - to be spent over the next 18 months - would go into additional resources for cargo inspections, rapid diagnostic technology, surveillance and operational system enhancements.

"It is a devastating pest of stored grains and dried foods," Mr Littleproud said.

"However, like the brown marmorated stink bug, it has increasingly been found hitchhiking outside these food sources in containers and packaging."

The khapra beetle is second on Australia's priority plant pest list, and at the top of Australia's plant priority pest list for grains.

The beetle is native to India but has spread across large parts of the world.

Grain Growers chief executive David McKeon welcomed the fresh funding, saying it would help protect Australia's $14.2 billion grain industry.

"Being an island, we're free of many pests and diseases ... it's important to keep that pest-free status because there's a lot of market sensitivities in a lot of our key international grain markets," Mr McKeon told AAP.

"It's important we maintain the premium status of our grains.

"The risks faced by the Australian grain industry are increasing over time as we see increased container movements internationally."

Mr Littleproud also announced on Tuesday that more than 60,000 mail items had been intercepted by border authorities in 2020 due to biosecurity concerns, an increase of 3000 on the year before.

He said that between October 15 and November 24, some 422 mail items were seized as they contained commodities that risked khapra beetle proliferation.

Australian Associated Press