Dr Sidharth Kaushal

The loss of an S-400 system, though still relatively rare, will be a painful and expensive and humiliating hit to Russia's air defenses. Each S-400 battery comes with a price tag of around $200 million, Sidharth Kaushal, of the London-based Royal United Services Institute think tank, told Newsweek on Tuesday. "Of course, the system can be replaced but it is still not a trivial loss," said Kaushal.

Ukraine is deploying cluster munitions "quite effectively," White House national security spokesperson John Kirby said in mid-July. "They are actually having an impact on Russia's defensive formations and Russia's defensive maneuvering," he added. Cluster munitions are "very useful for clearing out large numbers of infantry," Sidharth Kaushal, a research fellow at the London-based Royal United Services Institute defense think tank told Newsweek ahead of the decision.

Russia has unveiled a new unguided "dumb" rocket, kitted out with a cluster warhead to scatter a wide area with submunitions as Moscow looks to improve its military capabilities in the face of Ukraine's ongoing counteroffensive. ... Cluster munitions are "very useful for clearing out large numbers of infantry," Sidharth Kaushal, a research fellow at the London-based Royal United Services Institute think tank, previously told Newsweek.