The euro rose against the dollar on Wednesday on cautious optimism that eurozone leaders may reach a deal to ease Greece's debt problems, though concerns remained that the fiscal crisis could spill over to other countries in the region.
French ministers said on Wednesday that European leaders were less divided than the media was reporting and were likely to reach an accord at the summit that will alleviate Greece's debt woes.
That still left the euro vulnerable to signs the debt crisis could still spread to larger countries like Italy and Spain but for now, investors focused on the positive.
The euro was last up 0.3 percent at $1.4198.
The dollar fell 0.4 percent against the yen to 78.76 yen, having backed off an intraday high of 79.31 yen, according to Reuters data.