Christine Lagarde has taken a step closer to becoming the new head of the International Monetary Fund (IMF) after her candidacy was formally backed by the US.The move by the US comes as the IMF's 24-strong board is meeting to agree on its new managing director.
Analysts say Ms Lagarde is now all but certain to beat her rival candidate, Mexico's Central Bank Governor Agustin Carstens.
The IMF has always had a European head.
US Treasury Secretary Timothy Geithner said: "Minister Lagarde's exceptional talent and broad experience will provide invaluable leadership for this indispensable institution at a critical time for the global economy."
Ms Lagarde also secured the support of Russia on Tuesday. She has already been backed by China and Europe.
Mr Carstens is being supported by Latin American nations, plus Canada and Australia.
In a convention dating back to the establishment of the IMF and the World Bank after World War II, a European has always held the top job at the IMF, while an American leads the World Bank.
However, the countries backing Mr Carstens have argued that it is time the IMF was led by a non-European.
The vacancy at the top of the IMF came after former managing director Dominique Strauss-Kahn was forced to resign last month after he was arrested in New York on charges of sexual assault.
Mr Strauss-Kahn denies the charges.