(CNN) -- In the face of an "uneven" economic recovery, members of the G20 meeting in Paris agreed Saturday that the international monetary system has proven "resilient, but vulnerabilities remain."
Delegates at the meeting of finance ministers and central bank governors cited in a communique issued at the end of their two-day meeting the need to prevent "disorderly movements" and "persistent misalignment" of exchange rates.
The global recovery is "strengthening, but is still uneven" and "downside risks remain," according to the communique.
Advanced countries still suffer high unemployment, and emerging economies are growing robustly, "some with signs of overheating," the group said in its communique.
During the gathering, U.S. Federal Reserve Chairman Ben Bernanke spoke on a panel of central bankers, including the heads of the European Central Bank, the Bank of England and the People's Bank of China, and said unbalanced flows of money between nations is again posing a risk to the global economy and financial stability.
He added that the uneven flow of funds into the United States from 2003 to 2007 was one of the key factors that led to the meltdown in financial markets in 2008.
The United States has long criticized China for keeping the value of its currency, the yuan, low. They argue that it makes prices of Chinese products artificially cheap, giving exporters there an unfair advantage.
In a statement to the G-20 on Saturday, U.S. Treasury Secretary Timothy Geithner said that while China had been allowing the yuan to appreciate some against the dollar, "China's currency remains substantially undervalued."
G-20 delegates also expressed concern about volatile commodity prices, which can affect the cost of food. Food prices are up almost 30% in the past year. Sugar and wheat prices have risen 20%, while fats and oils used in cooking jumped 22%, according to the World Bank.
"Our research shows higher global wheat prices have directly fed into sharp increases in domestic wheat prices in many countries," Robert Zoellick, president of the World Bank, said earlier this week.
"In just six months, prices for wheat rose by more than 50% in Kyrgyzstan; 45% in Bangladesh and 33% in Mongolia," he said.
The Group of 20 was established in 1999 to bring together industrialized and developing economies to promote global economic stability.