Former US central bank heads on Thursday called the internationalization of the Chinese currency Reminbi, RMB or the yuan, "a positive thing", saying it will motivate China to further open the market.

Federal Reserve Chair Janet Yellen, and former Fed Chairs Ben Bernanke, Paul Volcker and Alan Greenspan expressed this view when they discussed the U.S. economy and global monetary policy issues at the International House of New York.

Regarding the issue of RMB internationalization, Greenspan said China has made extraordinary progress and evidences show that the RMB is getting closer to becoming a floating currency.

However, he pointed out that the total amount of holdings of the RMB in international reserves is "relatively small," so its internationalization process might still have a long way to go.

Volcker thinks the RMB becoming an international currency reflects the openness of the Chinese economy. "It's good for the world," he said.

Bernanke believes RMB internationalization will motivate China to further open its market, reform its financial market, increase liquidity and strengthen regulation, which is "a positive thing."