Ukraine has reportedly carried out its first strike on Russian territory using U.S.-supplied ATACMS missiles, marking a significant shift in the 1,000-day conflict. The strike, which targeted an ammunition depot in Russia's Bryansk region, followed the Biden administration’s decision to lift restrictions on the use of the long-range weaponry. Simultaneously, Russian President Vladimir Putin signed an updated nuclear doctrine, lowering the threshold for the use of atomic weapons if Russia is attacked by a non-nuclear state supported by a nuclear power. While Kyiv maintains that these capabilities are necessary to disrupt Russian military logistics, Moscow has warned that the move represents a direct escalation involving NATO. International leaders at the G20 summit in Brazil have expressed concern over the developments, with many calling for urgent de-escalation to avoid a wider global confrontation.