Task: Question Generation
Input (English): As many Japanese had feared, Japan's supply arrangements could not maintain her forces. Once Mutaguchi's hopes for an early victory were thwarted, his troops, particularly those at Kohima, starved. During May, while Mutaguchi continued to order attacks, the Allies advanced southwards from Kohima and northwards from Imphal. The two Allied attacks met on 22 June, breaking the Japanese siege of Imphal. The Japanese finally broke off the operation on 3 July. They had lost over 50,000 troops, mainly to starvation and disease. This represented the worst defeat suffered by the Japanese Army to that date.[citation needed]
Output (English): When was the Japanese siege of Imphal broken?