MOSCOW, June 21 (Xinhua) -- China has played a role of great importance during the founding and development of G20, Russian presidential aide Arkady Dvorkovich said on Monday.

"Without China's participation, it would be much more difficult for the group to discuss or solve the developmental problems of world economy. Therefore, the participation of China, as well as some other emerging economies like Brazil and India, has become prominently significant," Dvorkovich commented after a news conference ahead of the upcoming G8 and G20 summit in Toronto, Canada.

The presidential aide said the Chinese leaders' stance and viewpoints, proposed in the previous three G20 financial summit since November 2008, have helped stabilize the world economy as a whole.

Dvorkovich noted that China's decision on further exchange rate reform was not outcome of external pressure.

He said that any country, including Russia, China and the United States, could not allow their domestic policies to be ruled by external factors. The nations, however, should understand the common and mutual responsibilities in the global economic system.

The delegates to the G20 summit will adjust their polices after consultations, but nobody will bend under pressure, he stressed.

Dvorkovich said that several countries may voice concerns over China's exchange rate policies at the summits, but there will not be large-scale discussions over the Chinese currency.

The People's Bank of China, China's central bank, announced on Saturday a decision to proceed further with the reform of the exchange rate regime to enhance the flexibility of the RMB's exchange rate.