Ukraine used interceptor systems to shoot down more than 33,000 Russian drones of various types in March, a record monthly figure since Moscow launched its all-out invasion more than four years ago, Ukraine’s defense minister claimed.

Ukraine has escalated its long-distance strike campaign against Russian oil facilities in an effort to stop Moscow gaining a financial windfall from a U.S. waiver on sanctions amid global supply restrictions caused by the Iran war, according to the Institute for the Study of War, a Washington-based think tank.