The euro rallied today to trade above $1.40 for the first time since February on persistent concerns about the US economy's uncertain outlook. Earlier, the European Commission said the rise of the euro is 'disproportionate' and could affect economic recovery across the zone. 'We consider that the euro is currently bearing a disproportionate burden in the adjustment of the global exchange rate,' said commission spokesman Amadeu Altafaj. He said this may affect the European economy's recovery. Mr Altafaj also reiterated that China's yuan was 'still significantly undervalued'. The euro's latest rise came as the US currency reached a 15-year low point against the yen on persistent concern about the US economic outlook. Currency traders were also digesting comments from International Monetary Fund head Dominique Straus-Kahn, who said he took the threat of a currency war 'very seriously' and would do all he could to prevent one.