A senior Soviet military official says retreating Russian troops will not return to their former bases to rescue allied Afghan forces being attacked by Moslem rebels.

The official, in an interview Monday with United Press International, said the Soviet Union was determined to abide strictly by U.N.-mediated accords signed April 14 in Geneva providing for the Soviet withdrawal from Afghanistan that began May 15.Speaking on condition of anonymity, the official also disclosed for the first time that some 10,000 Soviet troops have been withdrawn from eastern Nangahar Province via its capital of Jalalabad since the beginning of the Soviet withdrawal. That province borders Pakistan.

The third and final column of troops to depart Jalalabad, about 90 miles east of Kabul and astride the main supply route to the capital from Pakistan, arrived in the city Sunday and left Monday in about 200 vehicles for the three-day drive to the Soviet border.

Western diplomats have been pondering whether Soviet military commanders would send their troops back if Afghan army garrisons become besieged by rebels.