Farmers spruik need for foreign investment

The National Farmers' Federation warns without greater clarity around foreign investment rules, potential buyers from overseas will throw up their hands, to the detriment of Australia.

Its chief executive Tony Mahar says the federal government needs to gain the trust of the Australian public with a clear national interest test that is properly explained.

"They need to provide leadership and invest in greater transparency around the screening process. To fail at this will be to constrain our nation's growth and place clear limitations on industries, like agriculture, which have potential to thrive to the benefit of all Australians," he writes in the Australian Financial Review on Tuesday.

Nationals leader Barnaby Joyce disagrees with Mr Mahar, saying foreign investment is actually increasing.

"There are people lined up wanting to buy Australian farmland," he told ABC radio.

"We have the right to say 'yes', but by gosh we have the right to say 'no' too."

He denied the suggestion if Australia said 'no' once or twice it would have an insidious effect on the price of real estate, labelling that "a load of codswallop".

"I have great respect for the NFF and Tony Mahar is a great bloke, but if we gave complete transparency on security details of Australia on national television and national radio I don't think that would serve the purpose that we have the national security committee for," Mr Joyce said.