Finance ministers and central bankers from the world's 20 leading industrial and developing countries have pledged not to target their exchange rates for competitive purposes.
The two-day meeting in Moscow ended with a joint communique that included a promise that the G20 members would "refrain from competitive devaluation" and "resist all forms of protectionism and keep our markets open."
Markets have been concerned by developments affecting the Japanese yen, which now trades near a three-year low. Japan is facing charges that it is trying first and foremost to lower the value of the yen to stimulate its economy and get the edge over other countries.
If too many countries try to weaken their currencies for economic gain — sparking a so-called "currency war" —the fragile global recovery could be derailed.