RAWALPINDI, Pakistan, Nov. 25 (AP) — The Soviet Union has delivered a note demanding that the Pakistani Government come to political terms with Bengali insurgents battling for the independence of East Pakistan, informed sources said today.

The Soviet Ambassador, Aleksei A. Rodionov, met President Agha Mohammad Yahya Khan after the President declared a national emergency. Pakistan asserts that India is attacking in East Pakistan.

The United States and the Soviet Union have been reported to be trying to confine the fighting in East Pakistan to prevent a wider war.

Foreign Office sources said the Soviet Union's friendship and security treaty with India, signed in October, left the United States as the only nonaligned major power able to seek an end to the fighting.