Massive drone strikes on Moscow left a trail of destruction in residential areas in Ukraine’s largest ever attack on the city according to local officials. The attacks come as the U.S. and Ukraine delegations are engaged in pivotal negotiations in Saudi Arabia over a possible minerals deal in exchange for security guarantees.

Russian air defenses shot down over 300 Ukrainian drones over 10 Russian regions overnight, military officials said Tuesday, in what appeared to be the biggest Ukrainian drone attack on Russia in the three-year war.