PARIS- France will keep pushing for a deal between Athens and the rest of the euro zone before Greece's referendum, France's finance minister said, hours before finance ministers from the region hold their second conference call on the crisis in two days.Last-minute overtures by Athens to international creditors for financial aid on Tuesday were not enough to save the country from becoming the first developed economy to default on a loan with the International Monetary Fund."Our aim is to find an agreement, before the referendum if possible," Michel Sapin told RTL radio on Wednesday, referring to the plebiscite on Sunday when Greeks will vote on whether to accept the austerity terms of continued international aid. "It's obviously frighteningly complicated."It is unclear how much the Wednesday Eurogroup conference call can achieve. Many members are skeptical about Athens' latest offers and German Chancellor Angela Merkel has ruled out further negotiations until after the referendum.