Leaders of the G20 grouping of main world economies are gathering in the South Korean capital Seoul amid international controversy over whether some countries are deliberately devaluing their currencies.
Both the United States and China face criticism over actions that have weakened their currencies and consequently made other countries less competitive.
Meanwhile, a US presidential commission has proposed drastic changes to tackle problems with the American economy.
The bipartisan commission has suggested making significant cuts to the country's budget deficit by 2020.
The proposal includes reducing social benefits, raising the retirement age and changing the tax system.