O'Neill and several PNG government ministers visited Beijing for a Belt and Road forum which brought together dozens of heads of state to discuss co-operation in China's trillion-dollar global infrastructure drive.
O'Neill says that improving infrastructure and supply chains is essential for PNG to increase agricultural and other forms of production for export and that PNG needs to strengthen its linkages with partner countries to make transportation more efficient.
O'Neill stressed that infrastructure development was vital to opening up opportunity for PNG's mainly rural population.
"In Papua New Guinea we have some of the most fertile soil in the world that can grow a wide range of food plants and feed livestock, but we have trouble getting it to markets," O'Neill said.
"It is disheartening when our people harvest vegetables or fruit they do not make it to market in a condition that can be sold.
"But these challenges can be overcome through a much more co-ordinated approach to the development of infrastructure and capacity building."
Meanwhile, Xinhua reported that the prime minister met with a senior Communist Party of China official, Zhao Leji, who said bilateral relations with PNG have become a model for China's relations with Pacific island countries.
He said China was willing to work together with PNG on the Belt and Road Initiative with the Melanesian country's development plans, so as to benefit peoples of the two countries through pragmatic cooperation.