At 3:00 AM on September 6, 1965, without the formal declaration of war, Indians crossed the international border of West Pakistan and launche a three-pronged offensive against Lahore, Sialkot and Rajasthan. There was a fierce tank battle on the plains of Punjab. The domestic Indo-Pak conflict transforme into an international conflict and raised Super Power concerns.
The U.S suspended military supplies to both sides during the Indo Pak War. Both the Soviet Union and the United States took a united stand to curtail the conflict within the boundaries of the Sub-continent from escalating into a global conflict. China threat to intervene and offer military support to Pakistan. It was to keep China away from this conflict that both the Soviet Union and the United States pressure the U.S to arrange for an immediate ceasefire.