Assigned to construction operations in Thailand, the division was ordered to Burma to join the Fifteenth Army in September, 1943. The Japanese plan to invade India, codenamed U-Go, was originally intended as a spoiling attack against the IV Corps at Imphal, to disrupt the Allied offensive plans for that year. The commander of the Fifteenth Army was none other than his old nemesis Lieutenant General Renya Mutaguchi. Despite the objections of his staff, Mutaguchi enlarged the plan to include an invasion of India itself and perhaps even overthrow the British Raj. Despite reports to Tokyo from his subordinates on the infeasibility of the plan, the objections were eventually overruled by Army Minister Hideki Tōjō. Part of the plan involved sending the 31st Division (which was composed of 58th, 124th, and 138th Regiments, and the 31st Mountain Artillery Regiment) to capture Kohima and thus cut off Imphal, and then destroy the rail yard at Dimapur. Divisional commander Satō was unhappy with his role. He had not been involved in the planning of the offensive and seriously doubted the Japanese chances for success; he had already told his staff that they might all starve to death, as Mutaguchi made no provision for logistics or resupply. In common with many senior Japanese officers, Satō considered Mutaguchi to be a "blockhead", although General William Slim considered Satō himself to be By the middle of May, Sato's troops were starving as had been predicted. He considered that Mutaguchi and the HQ of Japanese Fifteenth Army were taking little notice of his situation, as they had issued several confusing and contradictory orders to him during April. Because the main attack on Imphal faltered around the middle of April, Mutaguchi ordered 31st Division or parts of it to join in the attack on Imphal from the north, even while the division was struggling to capture and hold Kohima. Satō considered that his division was being "messed around" without proper planning or consideration for the conditions. Nor did Satō believe that Fifteenth Army headquarters were exerting themselves to move supplies to his division. He began pulling his troops back to conserve their strength, thus allowing the British to secure Kohima Ridge. On 25 May, Satō notified Fifteenth Army HQ that he would withdraw on 1 June unless his division received supplies. Finally on 31 May, he abandoned positions north of the road, in spite of orders from Mutaguchi