The Nationals Senator for New South Wales John Williams has accepted a challenge  from Greens member Lee Rhiannon to a debate on who really cares for regional Australia.

Senator Williams has accused Ms Rhiannon, a former member of the Socialist Party, of changing her tune on farming and is now pretending to care about food security to help her bid to win a seat in the Senate.

He said he is happy to debate her at AgQuip next week, but suggests she should consider an offer from his Nationals Senate colleague Senator Fiona Nash.

"Senator Nash is seeking re-election to the Senate and would love to go head to head with the person who wants her spot.

I'm sure those at AgQuip will remember the past Greens policies that have adversely affected  their ability to make a living on the land , and to hear of the Greens current radical policies that include death duties and fishing bans.

Ms Rhiannon can take her pick. Debate Senator Nash or me in front of a good gathering of farmers at AgQuip", Senator Williams said.