諾門罕戰役
On 14 September, with Poland's collapse at hand, the first statements on a conflict with Poland appeared in the Soviet press. The undeclared war between the Soviet Union and the Empire of Japan at the Battles of Khalkhin Gol had ended with the Molotov–Tojo agreement, signed on 15 September as a ceasefire took effect on 16 September. On 17 September, Molotov delivered a declaration of war to Wacław Grzybowski, the Polish Ambassador in Moscow: