The controversial truce between the Soviets and the mujahideen resistance in Afghanistan's Panjshir Valley may soon be drawing to an end. Unconfirmed reports from resistance and Western diplomatic sources indicate renewed fighting in the Shomali region just north of Kabul.
And according to sources cited by Western diplomats in Islamabad, the cease-fire, which was agreed to by Panjshir Valley commander Ahmad Shah Massoud and the Soviet high command last January, is not expected to last into the autumn. ''If they don't break it, then we will,'' a Massoud lieutenant said.
Although the truce was intended to remain in effect for only six months, both sides have till now continued to respect the arrangement. But when the Soviets recently tried to formally prolong the cease-fire, the Panjshiri rebels refused. Instead, they apparently demanded that the command post at the base of the valley be withdrawn.
Guerrilla groups cooperating with Massoud are also said to have stepped up their assaults against the Soviets on the strategic Salang highway along the northern border and in the vicinity of Bagram air base, one of Moscow's most important military installations in Afghanistan. In response, Soviet-Afghan planes and helicopters launched two attacks against surrounding resistance positions.
The Panjshir cease-fire was the first to be directly negotiated with the Soviets, although temporary truces or ''understandings'' have often been arranged in various parts of Afghanistan between the mujahideen (''holy warriors'') and government troops.
Since the Soviet invasion of Afghanistan in December 1979, the Panjshir has suffered six major offensives. Last year, two combined Soviet-Afghan assaults involving massive air and armored support - the first in May, the second in August - devastated much of the valley. Hundreds of families were forced to seek haven in rocky mountain retreats. Countless others fled on foot as refugees to the capital of Kabul and to Pakistan.
By Christmas of 1982, much of the Panjshir lay in ruins. Civilian and guerrilla casualties figured in the thousands. Up to four-fifths of the valley's mainly mud and stone dwellings had been reduced to rubble.
The attackers also ruptured irrigation channels, chopped down fruit trees, and machine-gunned cattle and sheep. Many farmers, except those in the upper regions of the valley, were unable to plant new crops. With little to harvest, the remaining 40,000 to 50,000 inhabitants faced serious food shortages.
Nevertheless, despite such havoc, resistance units continued to harass the communist forces throughout the two campaigns. According to guerrilla sources as well as Western journalists visiting the region last year, Soviet and Afghan government losses including defections were severe.
Soviet attempts to reassert government control failed as Afghan military positions left behind to garrison the valley fell one by one to guerrilla attacks.
Late last year, in an effort to end the stalemate and establish a modus vivendi with the Panjshiris, senior Afghan officials reportedly sent letters to Massoud requesting a cease-fire. This offer the guerrillas summarily rejected, maintaining that the Kabul regime ''has no power at all, so it is useless to speak with them.''
Overriding the Kabul authorities, the Soviets themselves decided to approach Massoud for a truce toward the end of December. According to several well-informed sources, this has caused considerable concern among Afghan government officials who fear that Moscow might start making a habit of elaborating its own deals with the guerrillas.
As a gesture of ''good faith,'' the Soviets unilaterally observed their own cease-fire by halting daily bombardments and confining their troops to camp. Massoud consulted with the valley's religious leaders and local resistance councils before agreeing to enter into negotiations.
In early January, a high-ranking Russian official entered guerrilla territory not far from the last government outpost to meet personally with the young Panjshiri commander.
Tense bargaining over tea in the customary Afghan manner resulted in the six-month mutual cease-fire. As part of the agreement, the Soviets were assured a peaceful withdrawal of all their forces. As the troops pulled out, the Panjshiri rebels moved back in.
Despite virulent criticism among certain Afghan circles both inside and outside the country that Massoud has sold himself to the Soviets, the Panjshiris argue that in agreeing to direct talks, Moscow has given de facto recognition to the resistance.
''It has also set a precedent for direct Soviet-Afghan talks, should the Russians ever be really serious about withdrawing from our country,'' said Professor Rabbani, head of Massoud's own Jamiat-e Islam Party.
More important for the Panjshiris, the truce has enabled the Panjshiris to rebuild their homes, cultivate their fields, and restock with desperately needed supplies. Shops are full once again and the road to Kabul was opened to the inhabitants without restriction.
By establishing a truce with Massoud, the Soviets were hoping to achieve at least two objectives. First, in a rudimentary manner, to show the Panjshiris that material gains could be obtained through peace with the government. Second, to show that even the most reputed guerrilla commanders are willing to talk with the Soviets, thereby attracting further candidates or sowing dissension among resistance ranks.
But Massoud contends that he has gained the advantage by using the respite to reorganize his forces. He has also taken the opportunity to tour the northern areas of Afghanistan to meet with local resistance commanders, some of whom he had trained over the past few years.