As negotiations continue for a new European Central Bank treaty, the German Bundesbank is calling for an option to sell 600 tons of gold from its gold reserves in order to fund federal research and education programs, a bank spokeswoman confirmed on Wednesday. The existing five-year treaty of the 15 members of the European Central Bank consortium limits the permitted annual sale of gold for all banks at 400 tons. However, the treaty expires in September and Germany wants to increase the limit.