Moscow appears to be keeping its promise to remove half its troops from Afghanistan by Monday, but Moslem insurgents seem behind schedule in retaking the war-torn country.

U.S. officials in Islamabad said it is likely that 50,000 Red Army soldiers will have crossed the Oxus River into Soviet territory by the Aug. 15 target date, three months after the withdrawal began."It appears they're holding to their obligation," said one U.S. diplomat. "But we obviously don't have detailed statistics."

The Soviets entered Afghanistan in December 1979 to help Afghanistan's communist government battle the U.S.-backed guerrillas. The Soviet pullout is to be completed by Feb. 15 under an accord signed in April in Geneva.

Many analysts predicted in April that the guerrillas would recapture Afghan cities as fast as they were handed over to government security forces.

But latest reports indicate almost all 30 provincial capitals remain in communist hands.

"Our aim is to take the provincial capitals but not at the cost of innocent lives," Azim Nasser-Zia, a spokesman of the Afghan Resistance Alliance, said Saturday.

The alliance of seven guerrilla groups is headed by Ahmad Syed Gailani of the National Islamic Front of Afghanistan. The guerrillas are also known as mujahedeen, or holy warriors.

Unconfirmed reports said combined guerrilla forces overran most of the northern provincial capital of Kunduz after Soviet troops moved out in the first week of August.

Sources also report that about 8,000 guerrillas are preparing to attack about 7,000 government forces defending the southeastern city of Kandahar, an ancient provincial capital.

Azim said Gailani was in Quetta, Pakistan, across the border from Kandahar, which the Soviets handed over to government troops in the first week of August.

Guerrillas have seized three other provincial capitals since May 15 but abandoned them days later under heavy Soviet aerial bombardment.

Many guerrilla leaders cautioned at the start of the Soviet withdrawal that key cities probably would not fall until after the nine-month pullout.

"When the Russians are gone then we can get what we really need, and that is the people's support," Azim said.