BERLIN (AP) — A major gas pipeline from Russia to Germany was shutting down for annual maintenance on Monday amid German concern that Russia may not resume the flow of gas as scheduled. The Nord Stream 1 pipeline, Germany’s main source of Russian gas, is scheduled to be out of action until July 21 for routine work that the operator says includes “testing of mechanical elements and automation systems.” The operator said the gas flow was reduced progressively starting at 6 a.m., German news agency dpa reported.