* USD strong across the board, USD/JPY at two week high. * Euro weak, may extend losses amid Greek uncertainty. * Aussie outlook weak after breaching important support. The euro held at four-month lows against the dollar on Wednesday and may extend losses sustained so far this month after Greece said it will hold new elections, raising risks Athens could eventually exit the euro. The prospect of prolonged political instability in the debt-ridden country is likely to keep the euro under severe pressure, analysts said. The common currency, which has already lost 4 percent in May, was barely changed from late New York ... (full story)