LONDON (Reuters) – Oil majors BP and Shell have held back on offering spot diesel cargoes in the market for the past two weeks, two traders sources with direct knowledge of the matter said, fearing potential shortages in Germany. Germany’s fuels and energy association on Thursday said that domestic supply can be maintained currently, but diesel and heating oil supplies are becoming more scarce. (Reporting by Julia Payne and Rowena Edwards in London; Christoph Steitz in Frankfurt; Editing by David Goodman)