Andreas George Papandreou, instructor in Economics, whose father's resignation from the Tsaldaris cabinet on Saturday overturned the Greek government, in an interview last night called forthright action by the United States--"forgetting formalities"--the key to Greek stability.

The 28-year-old. Papandreou has not seen his father, George Papandreou, erstwhile Minister of the Interior, since leaving Greece in 1940, but says he saw the present crisis coming from "a very good correspondence" he had kept up with his father.

Citing the Tsaldaris-led Populist government as "certainly not representative" under the meaning of the Marshall plan, Papandreou urged that the United States, whose presence minimizes the possibility of violent revolution, go ahead and decide the composition of a suitable government and then act to insure that such a government be established.

Papandreou arrived in the United States in October of 1940 to attend the Graduate School here and was married shortly thereafter. Two years later he became a teaching fellow in Economics and just before he entered the Navy was appointed an instructor in the same subject. His two and a half years in the Navy he describes as uneventful.