Published by Zeb BhamUS Treasury secretary Timothy Geithner has broken his silence on China's foreign exchange policy by rejecting the viability of devaluing currency to boost export trade.Speaking at the Commonwealth Club of California, Mr Geithner also declared that America would not take such action."It is very important for people to understand that the United States of America and no country around the world can devalue its way to prosperity, to [be] competitive," he told his audience.His comments come as G20 leaders prepare for next month's annual summit in Seoul, where currency strategy is expected to be the first item on the agenda.Brazil's finance minister Guido Mantega has also this week openly denounced the global "currency war" which has led to a 7.1 per cent gain in the real in the past three months.So too, Japan is also expected to call for a concerted rebalancing of global currency trading after announcing a solo forex purchasing programme last month to stem the rise of the yen.For more information on international payments, visit our Smart FX site.