By Stephanie Kelly NEW YORK (Reuters) -Oil prices jumped over $115 a barrel on Tuesday, their highest in about seven weeks, as the European Union kept pushing for a ban on Russian oil imports that would tighten supply. Prices retreated and were slightly lower after Reuters reported that sources said U.S. President Joe Biden’s administration will authorize as soon as Tuesday for U.S. oil company Chevron Corp to negotiate with Venezuelan President Nicolas Maduro’s government, temporarily lifting a ban on such discussions. “I don’t think that’s going to add a lot to the market anytime soon, but i…