Answer:
The two other nations asked to join in the founding of United Nations were China and France.
Step-by-step explanation:
The Yalta conference included the so-called 'big three' leaders. Roosevelt from the United States, Churchill from Great Britain and Stalin from the Soviet Union.
The conference was held so that all three great powers could decided the political future of Europe and maintain peace on the continent and all over the world.
No other country was invited in the conference. However, as the idea of a Untied Nations organisation was developed, Republic of China and France were seen as influential countries which could help drive the country forward.