China should publicly disclose what it pays African governments for extracting oil, gas and minerals as a way to level the playing field for companies worldwide and help countries get a fair deal for their natural resource wealth, billionaire investor George Soros said on Monday.

"China has to line up to join the regulations. Otherwise they are spoilers," Soros said at a forum on natural resources held on the sidelines of the U.S.-Africa Leaders Summit that runs through Wednesday.

Sub-Saharan Africa has immense riches in gold, gems and rare minerals and new discoveries of oil and gas off east Africa promise to make it a leading exporter of hydrocarbons by 2030. Yet its citizens see only a fraction of that wealth on a continent that has among the highest levels of poverty in the world.