The Prime Minister dropped in to hear some of the ideas for the future direction of rural communities at the 2020 summit.

He said delegates should contemplate if the intersection between unfolding global reality and national opportunities and challenges of the food space.

He said in his meeting with the president of the World Bank in Washington recently, most of their time was spent discussing food security.

"There are now 10 sets of major food riots erupting around the world, and if you look at the trajectories in terms of energy prices...the substitution and partial impact of biofuels, and also the impact of water scarcity and desertification, and the enduring strategic impact of the perversion of agricultural markets, frankly the world is in a bucket of strife on this front," Mr Rudd said.

"It's not episodic. The analysis of the World Bank is this is a deep and structural continuum.

"There you have a global problem, so where do we fit in in terms of a global solution and also national opportunities for ourselves.

"I am interested in your thinking on how we rise to the occasion."

Mr Rudd told the meeting he was working hard to get an outcome on Doha trade negotiations.

"If we do manage to get an outcome on Doha and we manage to get some liberalisation in terms of agricultural market access then the strategic challenge for us lies in the climate change/water challenge...

"Given the totality of those challenges, how do we craft a new set of long term national primary industry opportunities for Australia, mindful of the climate change and water challenge and mindful of the new opportunities which emerge and playing ourselves into the global game which is increasingly pointing to food undersupply?"

"Mr Rudd thanked those who had travelled from "very far and very wide" to be at the summit.