Afghans on Both Sides Maneuver for Power. RESISTANCE VS. RULING REGIME

IN the week since Soviet forces completed their withdrawal from Afghanistan, President Najibullah has moved to strengthen his beleaguered regime's grip on power. Even as the Soviet-installed leader promulgated emergency laws and headed up a new governing military council, his foes - the Pakistan-based Afghan resistance - were casting about for a united strategy to overthrow his regime and assume power.

On Monday, moderate resistance representatives reconvened, in Rawalpindi, Pakistan, with their hard-line fundamentalist colleagues in an attempt to bridge deep differences. A 400-member consultative council, known as a shura, failed to agree Sunday on naming a moderate as president and a fundamentalist as prime minister. Several gatherings of the shura in the past 12 days have become bogged down over power-sharing and the framework of a future Afghan government.

Western diplomats have urged resistance leaders to bury their differences in order to strengthen chances of ousting Najibullah. They believe a united interim mujahideen government could increase the chances of a military coup against Najibullah, and trigger defections by members of the Kabul regime to guerrilla ranks.

Pakistan, feeling the economic and political strains of hosting some 3 million Afghan refugees, is also urging a settlement that would result in the refugees leaving for home.

But whether or not the resistance can agree on a united political strategy, guerrillas as well as Western military observers and diplomats predict that the Najibullah government will not be able to survive long without active Soviet military support.

The Afghan guerrillas - chiefly armed and supported by the United States, China, Saudi Arabia, and Pakistan since the early 1980s - already control major roads leading to the capital, Kabul, and other large cities, as well as much of the eastern part of the country.

When declaring the state of emergency - which began three days after the Feb. 15 Soviet pullout - Najibullah cited it as a defense against ``conspiracies'' and ``armed intervention from outside.'' Under the emergency regulations civil rights - such as freedom of expression, privacy and public assembly - have been suspended.

Najibullah, a former head of the Afghan secret police, has also combined this tough stance with a fresh appeal for peace to his countrymen. In a 70-minute speech Sunday night, he called for peace talks, urged guerrilla commanders to go back to farming their lands, and invited refugees abroad to return home.

The People's Democratic Party of Afghanistan had dealt with the mistakes it had made in the past 10 years and would try not to repeat them, Najibullah said.

On Monday, Prime Minister Mohammad Hassan Sharq - who did not belong to the ruling communist party - resigned. His resignation followed a weekend shakeup of the Cabinet, in which Najibullah replaced seven non-party ministers with members of his party's central committee.