Answer:
Tehran
Step-by-step explanation:
The representants of the three major allies in the WWII conflict met to discuss key aspects during the war:
Stalin met with Churchil and Roosevelt in Tehran, Iran to set major strategies against the Nazis.
They agreed to keep the borders that were outlined secretly in the Nazi-Soviet pact, against the will of Poland government that at that time was in exile.
However, they also pressed for a revision of that border and they wanted to set it back to the 1920 boundaries as outlined by British Foreign Secretary.
The loss of territory of Poland then was to be compensated by moving it to the Oder and Neisse Rivers. After all, Poland, would by the end of WWII retake its former borders at the cost of German territory.