What was the planned Allied operation to invade the Kanto Plain near Tokyo in 1946 called?

Operation Coronet was the planned Allied invasion of the Kanto Plain near Tokyo in 1946.

Coronet formed the second phase of Operation Downfall, the proposed invasion of Japan’s home islands. Allied planners expected it to follow Operation Olympic, which was intended to seize southern Kyushu in November 1945. Coronet would then attack the Kanto Plain on Honshu, the main Japanese island, with Tokyo as the strategic objective.

The operation was planned for spring 1946 but was canceled when Japan surrendered. Its scale would have been enormous, requiring a huge concentration of Allied naval, air, and ground forces. The names are easy to mix up: Olympic concerned Kyushu, Coronet concerned the Tokyo region, and Downfall described the complete two-stage invasion plan. Operation Pastel was a deception plan associated with Olympic, not the main invasion of the Kanto Plain.